latex-dev (5may21)

git-svn-id: svn://tug.org/texlive/trunk@59080 c570f23f-e606-0410-a88d-b1316a301751

44 files changed, 2143 insertions, 623 deletions

diff --git a/Master/texmf-dist/tex/latex-dev/base/atbegshi-ltx.sty b/Master/texmf-dist/tex/latex-dev/base/atbegshi-ltx.sty
index ae05a7a297e..672479a434c 100644
--- a/Master/texmf-dist/tex/latex-dev/base/atbegshi-ltx.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/atbegshi-ltx.sty
@@ -47,7 +47,7 @@
 %%
 %%% From File: ltshipout.dtx
 \providecommand\ltshipoutversion{v1.0i}
-\providecommand\ltshipoutdate{2021/01/25}
+\providecommand\ltshipoutdate{2021/03/17}
 \ProvidesPackage{atbegshi-ltx}
    [2021/01/10 v1.0c
      Emulation of the original atbegshi^^Jpackage with kernel methods]
diff --git a/Master/texmf-dist/tex/latex-dev/base/atveryend-ltx.sty b/Master/texmf-dist/tex/latex-dev/base/atveryend-ltx.sty
index 543e9332dc5..663b13db340 100644
--- a/Master/texmf-dist/tex/latex-dev/base/atveryend-ltx.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/atveryend-ltx.sty
@@ -42,8 +42,8 @@
 %% and covered by LPPL is defined by the unpacking scripts (with
 %% extension .ins) which are part of the distribution.
 %%% From File: ltfilehook.dtx
-\providecommand\ltfilehookversion{v1.0g}
-\providecommand\ltfilehookdate{2021/02/08}
+\providecommand\ltfilehookversion{v1.0j}
+\providecommand\ltfilehookdate{2021/04/29}
 \ProvidesPackage{atveryend-ltx}
    [2020/08/19 v1.0a
      Emulation of the original atvery package^^Jwith kernel methods]
diff --git a/Master/texmf-dist/tex/latex-dev/base/fontenc.sty b/Master/texmf-dist/tex/latex-dev/base/fontenc.sty
index 0bf32c52c98..ecc422cfe8a 100644
--- a/Master/texmf-dist/tex/latex-dev/base/fontenc.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/fontenc.sty
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesPackage{fontenc}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
                         Standard LaTeX package]
 \def\update@uclc@with@cyrillic{%
  \expandafter\def\expandafter\@uclclist\expandafter
diff --git a/Master/texmf-dist/tex/latex-dev/base/latex.ltx b/Master/texmf-dist/tex/latex-dev/base/latex.ltx
index 2d22e178de4..942de9c0a35 100644
--- a/Master/texmf-dist/tex/latex-dev/base/latex.ltx
+++ b/Master/texmf-dist/tex/latex-dev/base/latex.ltx
@@ -12,10 +12,12 @@
 %% ltdefns.dtx  (with options: `2ekernel')
 %% ltcmd.dtx  (with options: `2ekernel')
 %% lthooks.dtx  (with options: `2ekernel')
+%% ltcmdhooks.dtx  (with options: `2ekernel')
 %% ltalloc.dtx  (with options: `2ekernel')
 %% ltcntrl.dtx  (with options: `2ekernel')
 %% lterror.dtx  (with options: `2ekernel')
 %% ltpar.dtx  (with options: `2ekernel')
+%% ltpara.dtx  (with options: `2ekernel')
 %% ltspace.dtx  (with options: `2ekernel')
 %% ltlogos.dtx  (with options: `2ekernel')
 %% ltfiles.dtx  (with options: `2ekernel')
@@ -484,6 +486,8 @@
     \errmessage{No room for a new #3}%
   \fi}
 \def\newhelp#1#2{\newtoks#1#1\expandafter{\csname#2\endcsname}}
+\newread\@inputcheck
+\newwrite\@unused
 \newdimen\maxdimen \maxdimen=16383.99999pt % the largest legal <dimen>
 \newskip\hideskip \hideskip=-1000pt plus 1fill % negative but can grow
 \newdimen\p@ \p@=1pt % this saves macro space and time
@@ -509,6 +513,12 @@
 \finalhyphendemerits=5000
 \adjdemerits=10000
 \tracinglostchars=1
+\ifx\directlua\@undefined
+  % \tracingstacklevels=0 % added in 2021
+\else
+  \newcount\tracingstacklevels
+  % Code for \tracingstacklevels defined in ltfinal.dtx
+\fi
 \uchyph=1
 \defaulthyphenchar=`\-
 \defaultskewchar=-1
@@ -633,54 +643,25 @@
 \gdef\loggingoutput{\tracingoutput\@ne
     \showboxbreadth\maxdimen\showboxdepth\maxdimen\errorstopmode}
 \gdef\showoutput{\loggingoutput\showoverfull}
-\ifx\tracingscantokens\@undefined
-\gdef\loggingall{%
-  \tracingstats\tw@
-  \tracingpages\@ne
-  \tracinglostchars\@ne
-  \tracingparagraphs\@ne
-  \errorcontextlines\maxdimen
-  \loggingoutput
-  \tracingmacros\tw@
-  \tracingcommands\tw@
-  \tracingrestores\@ne
-  }%
-\else
-\gdef\loggingall{%
+\edef\loggingall{%
   \tracingstats\tw@
   \tracingpages\@ne
-  \tracinglostchars\tw@
+  \tracinglostchars\thr@@
   \tracingparagraphs\@ne
   \tracinggroups\@ne
   \tracingifs\@ne
   \tracingscantokens\@ne
   \tracingnesting\@ne
   \errorcontextlines\maxdimen
-  \loggingoutput
+  \ifdefined\tracingstacklevels \tracingstacklevels\maxdimen \fi
+  \noexpand \loggingoutput
   \tracingmacros\tw@
   \tracingcommands\thr@@
   \tracingrestores\@ne
   \tracingassigns\@ne
 }%
-\fi
-\gdef\tracingall{\showoverfull\loggingall}
-\ifx\tracingscantokens\@undefined
-\def\tracingnone{%
-  \tracingonline\z@
-  \tracingcommands\z@
-  \showboxdepth\m@ne
-  \showboxbreadth\m@ne
-  \tracingoutput\z@
-  \errorcontextlines\m@ne
-  \tracingrestores\z@
-  \tracingparagraphs\z@
-  \tracingmacros\z@
-  \tracinglostchars\@ne
-  \tracingpages\z@
-  \tracingstats\z@
-}%
-\else
-\def\tracingnone{%
+\def\tracingall{\showoverfull\loggingall}
+\edef\tracingnone{%
   \tracingassigns\z@
   \tracingrestores\z@
   \tracingonline\z@
@@ -689,6 +670,7 @@
   \showboxbreadth\m@ne
   \tracingoutput\z@
   \errorcontextlines\m@ne
+  \ifdefined\tracingstacklevels \tracingstacklevels\z@ \fi
   \tracingnesting\z@
   \tracingscantokens\z@
   \tracingifs\z@
@@ -699,7 +681,6 @@
   \tracingpages\z@
   \tracingstats\z@
 }%
-\fi
 \def\hideoutput{%
   \tracingoutput\z@
   \showboxbreadth\m@ne
@@ -710,8 +691,8 @@
 %%% From File: ltvers.dtx
 \def\fmtname{LaTeX2e}
 \edef\fmtversion
-   {2021-05-01}
-\def\patch@level{-2}
+   {2021-06-01}
+\def\patch@level{-3}
 \edef\development@branch@name{develop \the\year-\the\month-\the\day}
 \iffalse
 \def\reserved@a#1/#2/#3\@nil{%
@@ -775,17 +756,37 @@
                 {There is an \string\EndIncludeRelease\space missing}%
   \@includeinreleasefalse
   \fi
-  \kernel@ifnextchar[%
-  {\@IncludeInRelease{#1}}
-  {\@IncludeInRelease{#1}[#1]}}
+  \ifnum0%
+      \ifx\new@moduledate\@empty\else 1\fi
+      \ifnum \expandafter\@parse@version#1//00\@nil=0 1\fi
+      =11
+    \expandafter\@firstoftwo
+  \else
+    \expandafter\@secondoftwo
+  \fi
+    {\finish@module@release{#1}}%
+    {\kernel@ifnextchar[%
+      {\@IncludeInRelease{#1}}
+      {\@IncludeInRelease{#1}[#1]}}}
+\def\finish@module@release#1#2#3{%
+  \toks@{[#1] #3}%
+  \ifnum\expandafter\@parse@version\new@moduledate//00\@nil
+       >\expandafter\@parse@version\fmtversion//00\@nil
+    \GenericInfo{}{Applying: \the\toks@}%
+  \else
+    \GenericInfo{}{Skipping: \the\toks@}%
+    \expandafter\gobble@finish@module@release
+  \fi}
+\long\def\gobble@finish@module@release#1\EndModuleRelease{%
+  \EndModuleRelease}
 \def\@IncludeInRelease#1[#2]{\@IncludeInRele@se{#2}}
 \def\@IncludeInRele@se#1#2#3{%
   \toks@{[#1] #3}%
   \expandafter\ifx\csname\string#2+\@currname+IIR\endcsname\relax
     \ifnum\expandafter\@parse@version#1//00\@nil
-          >\expandafter\@parse@version\fmtversion//00\@nil
+         >\expandafter\@parse@version\fmtversion//00\@nil
       \GenericInfo{}{Skipping: \the\toks@}%
-     \expandafter\expandafter\expandafter\@gobble@IncludeInRelease
+      \expandafter\expandafter\expandafter\@gobble@IncludeInRelease
     \else
       \GenericInfo{}{Applying: \the\toks@}%
       \@includeinreleasetrue
@@ -801,6 +802,9 @@
   \@includeinreleasefalse
 \else
   \PackageError{latexrelease}{mis-matched EndIncludeInRelease}{}%
+\fi
+\if@skipping@module
+  \expandafter\new@module@skip
 \fi}
 \long\def\@gobble@IncludeInRelease#1\EndIncludeInRelease{%
   \@includeinreleasefalse
@@ -810,6 +814,47 @@
                                    #2#3\@end@check@IncludeInRelease{%
   \ifx\@check@IncludeInRelease#2\else
     \PackageError{latexrelease}{skipped IncludeInRelease for tag \string#2}{}%
+  \fi
+  \if@skipping@module
+    \expandafter\new@module@skip
+  \fi}
+\let\if@skipping@module\iffalse
+\def\@skipping@moduletrue{\let\if@skipping@module\iftrue}
+\def\@skipping@modulefalse{\let\if@skipping@module\iffalse}
+\let\new@modulename\@empty
+\let\new@moduledate\@empty
+\def\NewModuleRelease#1#2#3{%
+  \ifx\new@modulename\@empty \else
+    \@latex@error{Nested \noexpand\NewModuleRelease forbidden.}\@ehd \fi
+  \edef\new@moduledate{#1}%
+  \edef\new@modulename{#2}%
+  \GenericInfo{}{BEGIN module: \new@modulename\space (\new@moduledate)}%
+  \GenericInfo{}{ \@spaces\@spaces\@spaces\space#3\@gobble}%
+  \ifnum\sourceLaTeXdate<%
+      \expandafter\@parse@version\new@moduledate//00\@nil\relax
+    \ifnum\expandafter\@parse@version\fmtversion//00\@nil<%
+          \expandafter\@parse@version\new@moduledate//00\@nil\relax
+      \GenericInfo{}{Skipping module \new@modulename}%
+      \expandafter\expandafter
+      \expandafter\gobble@finish@module@release
+    \else
+      \GenericInfo{}{Applying module \new@modulename}
+      \@skipping@modulefalse
+    \fi
+  \else
+    \GenericInfo{}{Skipping module \new@modulename}
+    \@skipping@moduletrue
+    \expandafter\new@module@skip
+  \fi}
+\long\def\new@module@skip#1\IncludeInRelease{\IncludeInRelease}
+\def\EndModuleRelease{%
+  \ifx\new@modulename\@empty
+    \@latex@error{Extra \string\EndModuleRelease.}\@eha
+  \else
+    \GenericInfo{}{END module: \new@modulename\space (\new@moduledate)}%
+    \let\new@modulename\@empty
+    \let\new@moduledate\@empty
+    \@skipping@modulefalse
   \fi}
 %%% From File: ltluatex.dtx
 \ifx\directlua\@undefined\else
@@ -991,8 +1036,12 @@
   }
 \fi
 %%% From File: ltexpl.dtx
-\let\@kernel@after@enddocument\@empty
-\let\@kernel@after@enddocument@afterlastpage\@empty
+\ifx\@kernel@after@enddocument\@undefined
+  \let \@kernel@after@enddocument               \@empty
+  \let \@kernel@after@enddocument@afterlastpage \@empty
+  \let \@kernel@before@begindocument \@empty
+  \let \@kernel@after@begindocument  \@empty
+\fi
 \def\reserved@a#1{\ifdefined#1\else\def#1{}\fi}
 \reserved@a\@expl@sys@load@backend@@
 \reserved@a\@expl@push@filename@@
@@ -1623,8 +1672,8 @@
     \xdef#1{\the\toks@}%
   \endgroup}
 %%% From File: ltcmd.dtx
-\def\ltcmdversion{v1.0a}
-\def\ltcmddate{2021/01/21}
+\def\ltcmdversion{v1.0d}
+\def\ltcmddate{2021-04-19}
 \message{document commands,}
 \ExplSyntaxOn
 \tl_new:N \l__cmd_arg_spec_tl
@@ -3330,7 +3379,7 @@
   }
 \cs_new_protected:Npn \__cmd_get_arg_spec:NTF #1#2#3
   {
-    \__cmd_cmd_if_xparse:NTF #1
+    \__kernel_cmd_if_xparse:NTF #1
       {
         \tl_set:Nx \ArgumentSpecification { \tl_item:Nn #1 { 2 } }
         #2
@@ -3430,7 +3479,7 @@
     #1 {#2} {#4}
     \__cmd_tl_mapthread_loop:w #1#3 \q_mark
   }
-\cs_new_protected:Npn \__cmd_cmd_if_xparse:NTF #1
+\cs_new_protected:Npn \__kernel_cmd_if_xparse:NTF #1
   {
     \exp_args:Nf \str_case_e:nnTF
       {
@@ -3883,8 +3932,9 @@
 \cs_new_eq:NN \ShowDocumentEnvironmentArgSpec \__cmd_show_arg_spec:n
 \ExplSyntaxOff
 %%% From File: lthooks.dtx
-\def\lthooksversion{v1.0h}
-\def\lthooksdate{2021/01/15}
+\def\lthooksversion{v1.0m}
+\def\lthooksdate{2021/04/29}
+
 \ExplSyntaxOn
 \bool_new:N \g__hook_debug_bool
 \cs_new_eq:NN \__hook_debug:n \use_none:n
@@ -3949,24 +3999,34 @@
 \cs_new_protected:Npn \__hook_tl_gclear:N #1
   { \__hook_tl_gset_eq:NN #1 \c_empty_tl }
 \cs_generate_variant:Nn \__hook_tl_gclear:N { c }
+
+
 \cs_new_protected:Npn \hook_new:n #1
   { \__hook_normalize_hook_args:Nn \__hook_new:n {#1} }
 \cs_new_protected:Npn \__hook_new:n #1
   {
-    \hook_if_exist:nTF {#1}
-      { \msg_error:nnn { hooks } { exists } {#1} }
+    \__hook_if_declared:nTF {#1}
+      { \__kernel_msg_error:nnn { hooks } { exists } {#1} }
+      {
+        \tl_new:c { g__hook_#1_declared_tl }
+        \__hook_make_usable:n {#1}
+      }
+  }
+\cs_new_protected:Npn \__hook_make_usable:n #1
+  {
+    \tl_if_exist:cF { __hook~#1 }
       {
         \seq_gput_right:Nn \g__hook_all_seq {#1}
         \tl_new:c { __hook~#1 }
-        \__hook_declare:n {#1}
-        \clist_new:c {g__hook_#1_labels_clist}
+        \__hook_init_structure:n {#1}
+        \clist_new:c { g__hook_#1_labels_clist }
         \tl_new:c { g__hook_#1_reversed_tl }
         \__hook_include_legacy_code_chunk:n {#1}
-     }
+      }
   }
-\cs_new_protected:Npn \__hook_declare:n #1
+\cs_new_protected:Npn \__hook_init_structure:n #1
   {
-    \__hook_if_exist:nF {#1}
+    \__hook_if_structure_exist:nF {#1}
       {
         \prop_new:c { g__hook_#1_code_prop }
         \tl_new:c { __hook_toplevel~#1 }
@@ -3994,6 +4054,44 @@
           }
       }
   }
+\cs_new_protected:Npn \hook_disable:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_disable:n {#1} }
+\cs_new_protected:Npn \__hook_disable:n #1
+  {
+    \tl_gclear_new:c { g__hook_#1_declared_tl }
+    \cs_undefine:c { __hook~#1 }
+  }
+\prg_new_conditional:Npnn \__hook_if_disabled:n #1 { p, T, F, TF }
+  {
+    \bool_lazy_and:nnTF
+        { \tl_if_exist_p:c { g__hook_#1_declared_tl } }
+        { ! \tl_if_exist_p:c { __hook~#1 } }
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\cs_new_protected:Npn \hook_provide:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_provide:nn {#1} {   } }
+\cs_new_protected:Npn \hook_provide_reversed:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_provide:nn {#1} { - } }
+\cs_new_protected:Npn \__hook_provide:nn #1 #2
+  {
+    \__hook_if_disabled:nTF {#1}
+      { \__kernel_msg_warning:nnn { hooks } { provide-disabled } {#1} }
+      {
+        \__hook_if_declared:nTF {#1}
+          {
+            \str_if_eq:eeF { \tl_use:c { g__hook_#1_reversed_tl } } {#2}
+              { \__kernel_msg_error:nnn { hooks } { provide-error } {#1} }
+          }
+          {
+            \tl_new:c { g__hook_#1_declared_tl }
+            \__hook_make_usable:n {#1}
+            \tl_gset:cn { g__hook_#1_reversed_tl } {#2}
+          }
+      }
+  }
+\cs_new_protected:Npn \hook_provide_pair:nn #1#2
+  { \hook_provide:n {#1} \hook_provide_reversed:n {#2} }
 \cs_new:Npn \__hook_parse_label_default:n #1
   {
     \tl_if_novalue:nTF {#1}
@@ -4004,7 +4102,7 @@
   {
     \tl_if_empty:nTF {#1}
       {
-        \msg_expandable_error:nn { hooks } { empty-label }
+        \__kernel_msg_expandable_error:nn { hooks } { empty-label }
         \__hook_currname_or_default:
       }
       {
@@ -4032,7 +4130,7 @@
       {
         \tl_if_empty:NTF \@currname
           {
-            \msg_expandable_error:nnn { hooks } { should-not-happen }
+            \__kernel_msg_expandable_error:nnn { hooks } { should-not-happen }
               { Empty~default~label. }
             \__hook_make_name:n { label-missing }
           }
@@ -4089,12 +4187,16 @@
         \__hook_if_marked_removal:nnTF {#1} {#2}
           { \__hook_unmark_removal:nn {#1} {#2} }
           {
-            \hook_if_exist:nTF {#1}
+            \__hook_if_usable:nTF {#1}
               {
                 \__hook_hook_gput_code_do:nnn {#1} {#2} {#3}
                 \__hook_update_hook_code:n {#1}
               }
-              { \__hook_try_declaring_generic_hook:nnn {#1} {#2} {#3} }
+              {
+                \__hook_if_disabled:nTF {#1}
+                  { \__kernel_msg_error:nnn { hooks } { hook-disabled } {#1} }
+                  { \__hook_try_declaring_generic_hook:nnn {#1} {#2} {#3} }
+              }
           }
       }
   }
@@ -4102,17 +4204,17 @@
 \cs_new_protected:Npn \__hook_hook_gput_code_do:nnn #1 #2 #3
   {
     \__hook_debug:n{\iow_term:x{****~ Add~ to~
-                      \hook_if_exist:nF {#1} { undeclared~ }
+                      \__hook_if_usable:nF {#1} { undeclared~ }
                       hook~ #1~ (#2)
                       \on@line\space <-~ \tl_to_str:n{#3}} }
     \str_if_eq:nnTF {#2} { top-level }
       {
         \str_if_eq:eeTF { top-level } { \__hook_currname_or_default: }
           {
-            \__hook_declare:n {#1}
+            \__hook_init_structure:n {#1}
             \__hook_tl_gput_right:cn { __hook_toplevel~#1 } {#3}
           }
-          { \msg_error:nnn { hooks } { misused-top-level } {#1} }
+          { \__kernel_msg_error:nnn { hooks } { misused-top-level } {#1} }
       }
       {
         \prop_get:cnNTF { g__hook_#1_code_prop } {#2} \l__hook_return_tl
@@ -4125,7 +4227,7 @@
   }
 \cs_new_protected:Npn \__hook_gput_undeclared_hook:nnn #1 #2 #3
   {
-    \__hook_declare:n {#1}
+    \__hook_init_structure:n {#1}
     \__hook_hook_gput_code_do:nnn {#1} {#2} {#3}
   }
 \cs_new_protected:Npn \__hook_try_declaring_generic_hook:nnn #1
@@ -4161,7 +4263,12 @@
       {
         \prop_if_in:NnTF \c__hook_generics_prop {#1}
           {
-            \hook_if_exist:nF {#5} { \hook_new:n {#5} }
+            \__hook_if_usable:nF {#5}
+              {
+                \str_if_eq:nnT {#1} { cmd }
+                  { \__hook_try_put_cmd_hook:n {#5} }
+                \__hook_make_usable:n {#5}
+              }
             \prop_if_in:NnTF \c__hook_generics_reversed_ii_prop {#2}
               { \tl_gset:cn { g__hook_#5_reversed_tl } { - } }
               {
@@ -4201,7 +4308,7 @@
       { \__hook_strip_double_slash:w #1/#2/#3 / #4 \s__hook_mark }
   }
 \prop_const_from_keyval:Nn \c__hook_generics_prop
-  {env=,file=,package=,class=,include=}
+     {cmd=,env=,file=,package=,class=,include=}
 \prop_const_from_keyval:Nn \c__hook_generics_reversed_ii_prop {after=,end=}
 \prop_const_from_keyval:Nn \c__hook_generics_reversed_iii_prop {after=}
 \prop_const_from_keyval:Nn \c__hook_generics_file_prop {before=,after=}
@@ -4209,7 +4316,7 @@
   { \__hook_normalize_hook_args:Nnn \__hook_gremove_code:nn {#1} {#2} }
 \cs_new_protected:Npn \__hook_gremove_code:nn #1 #2
   {
-    \__hook_if_exist:nTF {#1}
+    \__hook_if_structure_exist:nTF {#1}
       {
         \str_if_eq:nnTF {#2} {*}
           {
@@ -4227,7 +4334,7 @@
                       {#1} {#2}
               }
           }
-        \hook_if_exist:nT {#1}
+        \__hook_if_usable:nT {#1}
           { \__hook_update_hook_code:n {#1} }
       }
       { \__hook_mark_removal:nn {#1} {#2} }
@@ -4262,14 +4369,14 @@
   }
 \cs_new_protected:Npn \__hook_gset_rule:nnnn #1#2#3#4
   {
-    \__hook_declare:n {#1}
+    \__hook_init_structure:n {#1}
     \__hook_rule_gclear:nnn {#1} {#2} {#4}
     \cs_if_exist_use:cTF { __hook_rule_#3_gset:nnn }
       {
           {#1} {#2} {#4}
         \__hook_update_hook_code:n {#1}
       }
-      { \msg_error:nnnnnn { hooks } { unknown-rule }
+      { \__kernel_msg_error:nnnnnn { hooks } { unknown-rule }
                           {#1} {#2} {#3} {#4}        }
   }
 \cs_new_protected:Npn \__hook_rule_before_gset:nnn #1#2#3
@@ -4310,7 +4417,7 @@
   {
     \if_int_compare:w \__hook_str_compare:nn {#1} {#2} > 0 \exp_stop_f:
       \prg_return_true:
-    \else
+    \else:
       \prg_return_false:
     \fi:
   }
@@ -4344,7 +4451,7 @@
     \__hook_debug:n{ \iow_term:x{^^JUpdate~ code~ for~ hook~
                                     '#1' \on@line :^^J} }
     \__hook_include_legacy_code_chunk:n {#1}
-    \hook_if_exist:nT {#1}
+    \__hook_if_usable:nT {#1}
       {
         \prop_if_empty:cTF {g__hook_#1_code_prop}
           {
@@ -4488,7 +4595,7 @@
 \cs_new_protected:cpn { __hook_apply_rule_xE:nnn } #1#2#3
   {
     \__hook_debug:n { \__hook_msg_pair_found:nnn {#1} {#2} {#3} }
-    \msg_error:nnnnnn { hooks } { labels-incompatible }
+    \__kernel_msg_error:nnnnnn { hooks } { labels-incompatible }
       {#1} {#2} {#3} { 1 }
     \use:c { __hook_apply_rule_->:nnn } {#1} {#2} {#3}
     \use:c { __hook_apply_rule_<-:nnn } {#1} {#2} {#3}
@@ -4496,7 +4603,7 @@
 \cs_new_protected:cpn { __hook_apply_rule_xW:nnn } #1#2#3
   {
     \__hook_debug:n { \__hook_msg_pair_found:nnn {#1} {#2} {#3} }
-    \msg_warning:nnnnnn { hooks } { labels-incompatible }
+    \__kernel_msg_warning:nnnnnn { hooks } { labels-incompatible }
       {#1} {#2} {#3} { 0 }
   }
 \cs_new_protected:cpn { __hook_apply_rule_->:nnn } #1#2#3
@@ -4564,8 +4671,10 @@
   {
     \__hook_preamble_hook:n {#1}
     \__hook_log_cmd:x { ^^J ->~The~hook~'#1': }
-    \hook_if_exist:nF {#1}
-      { \__hook_log_line:x { is~not~declared! } }
+    \__hook_if_usable:nF {#1}
+      { \__hook_log_line:x { The~hook~is~not~declared. } }
+    \__hook_if_disabled:nT {#1}
+      { \__hook_log_line:x { The~hook~is~disabled. } }
     \hook_if_empty:nTF {#1}
       { #2 { The~hook~is~empty } }
       {
@@ -4579,7 +4688,7 @@
         \__hook_log_line:x
           {
             Document-level~(top-level)~code
-            \hook_if_exist:nT {#1}
+            \__hook_if_usable:nT {#1}
               { ~(executed~\__hook_if_reversed:nTF {#1} {first} {last} ) } :
           }
         \__hook_log_line_indent:x
@@ -4610,7 +4719,7 @@
         \bool_if:NT \l__hook_tmpa_bool
           { \__hook_log_line_indent:x { --- } }
         \bool_lazy_and:nnTF
-            { \hook_if_exist_p:n {#1} }
+            { \__hook_if_usable_p:n {#1} }
             { ! \hook_if_empty_p:n {#1} }
           {
             \__hook_log_line:x
@@ -4632,10 +4741,12 @@
               }
           }
           {
+            \__hook_log_line:x { Execution~order: }
             #2
               {
-                Hook~ \hook_if_exist:nTF {#1}
-                  {code~pool~empty} {not~declared}
+                \@spaces Not~set~because~the~hook~ \__hook_if_usable:nTF {#1}
+                  { code~pool~is~empty }
+                  { is~\__hook_if_disabled:nTF {#1} {disabled} {undeclared} }
               }
           }
       }
@@ -4691,10 +4802,14 @@
   { \__hook_normalize_hook_args:Nn \__hook_gput_next_code:nn {#1} }
 \cs_new_protected:Npn \__hook_gput_next_code:nn #1 #2
   {
-    \__hook_declare:n {#1}
-    \hook_if_exist:nTF {#1}
-      { \__hook_gput_next_do:nn {#1} {#2} }
-      { \__hook_try_declaring_generic_next_hook:nn {#1} {#2} }
+    \__hook_if_disabled:nTF {#1}
+      { \__kernel_msg_error:nnn { hooks } { hook-disabled } {#1} }
+      {
+        \__hook_init_structure:n {#1}
+        \__hook_if_usable:nTF {#1}
+          { \__hook_gput_next_do:nn {#1} {#2} }
+          { \__hook_try_declaring_generic_next_hook:nn {#1} {#2} }
+      }
   }
 \cs_new_protected:Npn \__hook_gput_next_do:nn #1
   {
@@ -4746,12 +4861,12 @@
   {
     \__hook_if_file_hook:wTF #1 / / \s__hook_mark
       {
-        \exp_args:Ne \__hook_if_exist_use:n
+        \exp_args:Ne \__hook_if_usable_use:n
           { \exp_args:Ne \__hook_file_hook_normalize:n {#1} }
       }
-      { \__hook_if_exist_use:n {#1} } % file/ generic hook (e.g. file/before)
+      { \__hook_if_usable_use:n {#1} } % file/ generic hook (e.g. file/before)
   }
-\cs_new_protected:Npn \__hook_if_exist_use:n #1
+\cs_new_protected:Npn \__hook_if_usable_use:n #1
   {
     \tl_if_exist:cT { __hook~#1 }
       {
@@ -4771,9 +4886,10 @@
   }
 \cs_new_protected:Npn \__hook_use_once_store:n #1
   { \prop_gput:Nnn \g__hook_execute_immediately_prop {#1} { } }
+
 \prg_new_conditional:Npnn \hook_if_empty:n #1 { p , T , F , TF }
   {
-    \__hook_if_exist:nTF {#1}
+    \__hook_if_structure_exist:nTF {#1}
       {
         \bool_lazy_and:nnTF
             { \prop_if_empty_p:c { g__hook_#1_code_prop } }
@@ -4787,18 +4903,24 @@
       }
       { \prg_return_true: }
   }
-\prg_new_conditional:Npnn \hook_if_exist:n #1 { p , T , F , TF }
+\prg_new_conditional:Npnn \__hook_if_usable:n #1 { p , T , F , TF }
   {
     \tl_if_exist:cTF { __hook~#1 }
       { \prg_return_true: }
       { \prg_return_false: }
   }
-\prg_new_conditional:Npnn \__hook_if_exist:n #1 { p , T , F , TF }
+\prg_new_conditional:Npnn \__hook_if_structure_exist:n #1 { p , T , F , TF }
   {
     \prop_if_exist:cTF { g__hook_#1_code_prop }
       { \prg_return_true: }
       { \prg_return_false: }
   }
+\prg_new_conditional:Npnn \__hook_if_declared:n #1 { p, T, F, TF }
+  {
+    \tl_if_exist:cTF { g__hook_#1_declared_tl }
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
 \prg_new_conditional:Npnn \__hook_if_reversed:n #1 { p , T , F , TF }
   {
     \if_int_compare:w \cs:w g__hook_#1_reversed_tl \cs_end: 1 < 0 \exp_stop_f:
@@ -4807,47 +4929,54 @@
       \prg_return_false:
     \fi:
   }
-\msg_new:nnnn { hooks } { labels-incompatible }
+\__kernel_msg_new:nnnn { hooks } { labels-incompatible }
   {
-    Labels~`#1'~and~`#2'~are~incompatible
-    \str_if_eq:nnF {#3} {??} { ~in~hook~`#3' } .~
+    Labels~'#1'~and~'#2'~are~incompatible
+    \str_if_eq:nnF {#3} {??} { ~in~hook~'#3' } .~
     \int_compare:nNnTF {#4} = { 1 }
       { The~ code~ for~ both~ labels~ will~ be~ dropped. }
       { You~ may~ see~ errors~ later. }
   }
   { LaTeX~found~two~incompatible~labels~in~the~same~hook.~
     This~indicates~an~incompatibility~between~packages.  }
-\msg_new:nnnn { hooks } { exists }
-    { Hook~`#1'~ has~ already~ been~ declared. }
+\__kernel_msg_new:nnnn { hooks } { exists }
+    { Hook~'#1'~ has~ already~ been~ declared. }
     { There~ already~ exists~ a~ hook~ declaration~ with~ this~
       name.\\
       Please~ use~ a~ different~ name~ for~ your~ hook.}
-\msg_new:nnn { hooks } { empty-label }
+\__kernel_msg_new:nnnn { hooks } { hook-disabled }
+  { Cannot~add~code~to~disabled~hook~'#1'. }
+  {
+    The~hook~'#1'~you~tried~to~add~code~to~was~previously~disabled~
+    with~\iow_char:N\\hook_disable:n~or~\iow_char:N\\DisableHook,~so~
+    it~cannot~have~code~added~to~it.
+  }
+\__kernel_msg_new:nnn { hooks } { empty-label }
   {
     Empty~code~label~\msg_line_context:.~
-    Using~`\__hook_currname_or_default:'~instead.
+    Using~'\__hook_currname_or_default:'~instead.
   }
-\msg_new:nnn { hooks } { no-default-label }
+\__kernel_msg_new:nnn { hooks } { no-default-label }
   {
     Missing~(empty)~default~label~\msg_line_context:. \\
     This~command~was~ignored.
   }
-\msg_new:nnnn { hooks } { unknown-rule }
-  { Unknown~ relationship~ `#3'~
-    between~ labels~ `#2'~ and~ `#4'~
-    \str_if_eq:nnF {#1} {??} { ~in~hook~`#1' }. ~
+\__kernel_msg_new:nnnn { hooks } { unknown-rule }
+  { Unknown~ relationship~ '#3'~
+    between~ labels~ '#2'~ and~ '#4'~
+    \str_if_eq:nnF {#1} {??} { ~in~hook~'#1' }. ~
     Perhaps~ a~ missspelling?
   }
   {
     The~ relation~ used~ not~ known~ to~ the~ system.~ Allowed~ values~ are~
-    `before'~ or~ `<',~
-    `after'~ or~ `>',~
-    `incompatible-warning',~
-    `incompatible-error',~
-    `voids'~ or~
-    `unrelated'.
+    'before'~ or~ '<',~
+    'after'~ or~ '>',~
+    'incompatible-warning',~
+    'incompatible-error',~
+    'voids'~ or~
+    'unrelated'.
   }
-\msg_new:nnnn { hooks } { misused-top-level }
+\__kernel_msg_new:nnnn { hooks } { misused-top-level }
   {
     Illegal~\iow_char:N \\AddToHook{#1}[top-level]{...}.\\
     'top-level'~is~reserved~for~the~user's~document.
@@ -4858,36 +4987,56 @@
     '\__hook_currname_or_default:'~for~this~\@cls@pkg,~or~another~
     suitable~label.
   }
-\msg_new:nnn { hooks } { set-top-level }
+\__kernel_msg_new:nnn { hooks } { set-top-level }
   {
-    You~cannot~change~the~default~label~#1~`top-level'.~Illegal \\
+    You~cannot~change~the~default~label~#1~'top-level'.~Illegal \\
     \use:nn { ~ } { ~ } \iow_char:N \\#2{#3} \\
     \msg_line_context:.
   }
-\msg_new:nnn { hooks } { ddhl-deprecated }
+\__kernel_msg_new:nnn { hooks } { ddhl-deprecated }
   {
     \iow_char:N \\DeclareDefaultHookLabel~is~deprecated.\\
     Use~\iow_char:N \\SetDefaultHookLabel~instead.\\ \\
     The~deprecated~name~will~be~removed~in~the~next~release.
   }
-\msg_new:nnn { hooks } { extra-pop-label }
+\__kernel_msg_new:nnn { hooks } { extra-pop-label }
   {
     Extra~\iow_char:N \\PopDefaultHookLabel. \\
     This~command~will~be~ignored.
   }
-\msg_new:nnn { hooks } { missing-pop-label }
+\__kernel_msg_new:nnn { hooks } { missing-pop-label }
   {
     Missing~\iow_char:N \\PopDefaultHookLabel. \\
-    The~label~`#1'~was~pushed~but~never~popped.~Something~is~wrong.
+    The~label~'#1'~was~pushed~but~never~popped.~Something~is~wrong.
   }
-\msg_new:nnn { hooks } { should-not-happen }
+\__kernel_msg_new:nnn { hooks } { should-not-happen }
   {
     ERROR!~This~should~not~happen.~#1 \\
     Please~report~at~https://github.com/latex3/latex2e.
   }
+\__kernel_msg_new:nnn { hooks } { provide-disabled }
+  {
+    Can't~ provide~ hook~ '#1'~ because~ it~ is~ disabled!
+  }
+\__kernel_msg_new:nnnn { hooks } { provide-error }
+  {
+    Hook~'#1'~ already~ declared~ as~ a~
+    \__hook_if_reversed:nTF {#1} { reversed } { normal }~ hook!
+  }
+  {
+    You~ attempted~ to~ provide~ the~ hook~'#1'~ as~ a~
+    \__hook_if_reversed:nTF {#1} { normal } { reversed }~ hook,~ but~ it~
+    was~ already~ previously~ declared~ as~ a~
+    \__hook_if_reversed:nTF {#1} { reversed } { normal }~ hook.~
+    A~ redeclaration~ is~ not~ possible.
+  }
 \NewDocumentCommand \NewHook             { m }{ \hook_new:n {#1} }
 \NewDocumentCommand \NewReversedHook     { m }{ \hook_new_reversed:n {#1} }
 \NewDocumentCommand \NewMirroredHookPair { mm }{ \hook_new_pair:nn {#1}{#2} }
+\NewDocumentCommand \ProvideHook         { m }{ \hook_provide:n {#1} }
+\NewDocumentCommand \ProvideReversedHook { m }{ \hook_provide_reversed:n {#1} }
+\NewDocumentCommand \ProvideMirroredHookPair { mm }{ \hook_provide_pair:nn {#1}{#2} }
+\NewDocumentCommand \DisableHook { m }{ \hook_disable:n {#1} }
 \NewDocumentCommand \AddToHook { m o +m }
   { \hook_gput_code:nnn {#1} {#2} {#3} }
 \NewDocumentCommand \AddToHookNext { m +m }
@@ -4900,11 +5049,11 @@
 \cs_new_protected:Npn \__hook_curr_name_push_aux:n #1
   {
     \tl_if_blank:nTF {#1}
-      { \msg_error:nn { hooks } { no-default-label } }
+      { \__kernel_msg_error:nn { hooks } { no-default-label } }
       {
         \str_if_eq:nnTF {#1} { top-level }
           {
-            \msg_error:nnnnn { hooks } { set-top-level }
+            \__kernel_msg_error:nnnnn { hooks } { set-top-level }
               { to } { PushDefaultHookLabel } {#1}
           }
           {
@@ -4917,7 +5066,7 @@
   {
     \seq_gpop:NNTF \g__hook_name_stack_seq \l__hook_return_tl
       { \tl_gset_eq:NN \g__hook_hook_curr_name_tl \l__hook_return_tl }
-      { \msg_error:nn { hooks } { extra-pop-label } }
+      { \__kernel_msg_error:nn { hooks } { extra-pop-label } }
   }
 \tl_gput_right:Nn \@kernel@after@enddocument@afterlastpage
   { \__hook_end_document_label_check: }
@@ -4925,7 +5074,7 @@
   {
     \seq_gpop:NNT \g__hook_name_stack_seq \l__hook_return_tl
       {
-        \msg_error:nnx { hooks } { missing-pop-label }
+        \__kernel_msg_error:nnx { hooks } { missing-pop-label }
           { \g__hook_hook_curr_name_tl }
         \tl_gset_eq:NN \g__hook_hook_curr_name_tl \l__hook_return_tl
         \__hook_end_document_label_check:
@@ -4935,7 +5084,7 @@
   {
     \seq_if_empty:NTF \g__hook_name_stack_seq
       {
-        \msg_error:nnnnn { hooks } { set-top-level }
+        \__kernel_msg_error:nnnnn { hooks } { set-top-level }
           { for } { SetDefaultHookLabel } {#1}
       }
       { \exp_args:Nx \__hook_set_default_label:n { \__hook_make_name:n {#1} } }
@@ -4944,14 +5093,14 @@
   {
     \str_if_eq:nnTF {#1} { top-level }
       {
-        \msg_error:nnnnn { hooks } { set-top-level }
+        \__kernel_msg_error:nnnnn { hooks } { set-top-level }
           { to } { SetDefaultHookLabel } {#1}
       }
       { \tl_gset:Nn \g__hook_hook_curr_name_tl {#1} }
   }
 \NewDocumentCommand \DeclareDefaultHookLabel { m }
   {
-    \msg_error:nn { hooks } { ddhl-deprecated }
+    \__kernel_msg_error:nn { hooks } { ddhl-deprecated }
     \SetDefaultHookLabel {#1}
   }
 \NewDocumentCommand \PushDefaultHookLabel { m }
@@ -4977,15 +5126,328 @@
 \@onlypreamble\DeclareDefaultHookRule
 \NewDocumentCommand \ClearHookRule { m m m }
 { \hook_gset_rule:nnnn {#1}{#2}{unrelated}{#3} }
-\cs_new_eq:NN \IfHookExistsTF \hook_if_exist:nTF
 \cs_new_eq:NN \IfHookEmptyTF \hook_if_empty:nTF
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5
+\cs_new_eq:NN \IfHookExistsTF \__hook_if_usable:nTF
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \cs_new_eq:NN \@expl@@@initialize@all@@
               \__hook_initialize_all:
 \cs_new_eq:NN \@expl@@@hook@curr@name@pop@@
               \__hook_curr_name_pop:
 \ExplSyntaxOff
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% File: ltcmdhooks.dtx (C) Copyright 2020-2021
+%%       Frank Mittelbach, Phelype Oleinik, LaTeX Team
+%%% From File: ltcmdhooks.dtx
+\def\ltcmdhooksversion{v1.0a}
+\def\ltcmdhooksdate{2021/04/30}
+\ExplSyntaxOn
+\tl_new:N \g_hook_patch_action_list_tl
+\int_new:N \l__hook_patch_num_args_int
+\tl_new:N \l__hook_patch_prefixes_tl
+\tl_new:N \l__hook_patch_param_text_tl
+\tl_new:N \l__hook_patch_replacement_tl
+\prop_new:N \g__hook_delayed_patches_prop
+\cs_new_protected:Npn \__hook_patch_debug:x #1
+  { \__hook_debug:n { \iow_term:x { [lthooks]~#1 } } }
+\cs_generate_variant:Nn \tl_rescan:nn { nV }
+\cs_new_protected:Npn \__hook_try_put_cmd_hook:n #1
+  { \__hook_try_put_cmd_hook:w #1 / / / \s__hook_mark {#1} }
+\cs_new_protected:Npn \__hook_try_put_cmd_hook:w
+    #1 / #2 / #3 / #4 \s__hook_mark #5
+  {
+    \__hook_debug:n { \iow_term:n { ->~Adding~cmd~hook~to~'#2'~(#3): } }
+    \str_case:nnTF {#3}
+        { { before } { } { after } { } }
+      { \exp_args:Nc \__hook_patch_cmd_or_delay:Nnn {#2} {#2} {#3} }
+      { \__kernel_msg_error:nnn { hooks } { wrong-cmd-hook } {#2} {#3} }
+  }
+\cs_new_protected:Npn \__hook_patch_cmd_or_delay:Nnn #1 #2 #3
+  {
+    \__hook_debug:n { \iow_term:n { ->~Add~generic~cmd~hook~for~#2~(#3). } }
+    \__hook_debug:n
+      { \iow_term:n { !~In~the~preamble:~delaying. } }
+    \prop_gput:Nnn \g__hook_delayed_patches_prop { #2 / #3 }
+      { \__hook_cmd_try_patch:nn {#2} {#3} }
+  }
+\cs_new_protected:Npn \__hook_cmd_begindocument_code:
+  {
+    \cs_gset_eq:NN \__hook_patch_cmd_or_delay:Nnn \__hook_patch_command:Nnn
+    \prop_map_function:NN \g__hook_delayed_patches_prop { \use_ii:nn }
+    \prop_gclear:N \g__hook_delayed_patches_prop
+    \cs_undefine:N \__hook_cmd_begindocument_code:
+  }
+\g@addto@macro \@kernel@after@begindocument
+  { \__hook_cmd_begindocument_code: }
+\cs_new_protected:Npn \__hook_cmd_try_patch:nn #1 #2
+  {
+    \__hook_debug:n
+      { \iow_term:x { ->~\string\begin{document}~try~cmd / #1 / #2. } }
+    \__hook_if_declared:nTF { cmd / #1 / #2 }
+      {
+        \__hook_debug:n
+          { \iow_term:n { .->~Giving~up:~hook~already~created. } }
+      }
+      {
+        \cs_if_exist:cT {#1}
+          { \exp_args:Nc \__hook_patch_command:Nnn {#1} {#1} {#2} }
+      }
+  }
+\cs_new_protected:Npn \__hook_patch_command:Nnn #1 #2 #3
+  {
+    \__hook_patch_debug:x { analyzing~'\token_to_str:N #1' }
+    \__hook_patch_debug:x { \token_to_str:N #1 = \token_to_meaning:N #1 }
+    \__hook_patch_check:NNnn \cs_if_exist:NTF #1 { undef }
+      {
+        \__hook_patch_debug:x { ++~control~sequence~is~defined }
+        \__hook_patch_check:NNnn \token_if_macro:NTF #1 { macro }
+          {
+            \__hook_patch_debug:x { ++~control~sequence~is~a~macro }
+            \__hook_patch_check:NNnn \__hook_if_public_command:NTF #1 { expl3 }
+              {
+                \__hook_patch_debug:x { ++~macro~is~not~private }
+                \robust@command@act
+                  \g_hook_patch_action_list_tl #1
+                  \__hook_retokenize_patch:Nnn { #1 {#2} {#3} }
+              }
+          }
+      }
+  }
+\cs_new_protected:Npn \__hook_patch_check:NNnn #1 #2 #3 #4
+  {
+    #1 #2 {#4}
+      {
+        \__kernel_msg_error:nnxx { hooks } { cant-patch }
+          { \token_to_str:N #2 } {#3}
+      }
+  }
+\use:x
+  {
+    \prg_new_protected_conditional:Npnn
+        \exp_not:N \__hook_if_public_command:N ##1 { TF }
+      {
+        \exp_not:N \exp_last_unbraced:Nf
+          \exp_not:N \__hook_if_public_command:w
+            { \exp_not:N \cs_to_str:N ##1 }
+          \tl_to_str:n { _ _ } \s__hook_mark
+      }
+  }
+\exp_last_unbraced:NNNNo
+\cs_new_protected:Npn \__hook_if_public_command:w
+    #1 \tl_to_str:n { _ _ } #2 \s__hook_mark
+  {
+    \tl_if_empty:nTF {#2}
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\tl_gset:Nn \g_hook_patch_action_list_tl
+  {
+    { \@if@DeclareRobustCommand \__hook_patch_DeclareRobustCommand:Nnn }
+    { \@if@newcommand \__hook_patch_newcommand:Nnn }
+    { \__kernel_cmd_if_xparse:NTF \__hook_cmd_patch_xparse:Nnn }
+  }
+\cs_new_protected:Npn \__hook_patch_DeclareRobustCommand:Nnn #1
+  {
+    \exp_args:Nc \@if@newcommand { \cs_to_str:N #1 ~ }
+      { \exp_args:Nc \__hook_patch_newcommand:Nnn }
+      { \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_false_bool }
+        { \cs_to_str:N #1 ~ }
+  }
+\cs_new_protected:Npn \__hook_patch_newcommand:Nnn #1
+  {
+    \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_true_bool
+      { \c_backslash_str \cs_to_str:N #1 }
+  }
+\cs_new_protected:Npn \__hook_cmd_patch_xparse:Nnn #1
+  {
+    \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_false_bool
+      { \cs_to_str:N #1 ~ code }
+  }
+\cs_new_protected:Npn \__hook_patch_expand_redefine:NNnn #1 #2 #3 #4
+  {
+    \__hook_patch_debug:x { ++~command~can~be~patched~without~rescanning }
+    \int_set:Nn \l__hook_patch_num_args_int
+      {
+        \exp_args:Nf \str_count:n { \cs_argument_spec:N #2 } / 2
+        \bool_if:NT #1 { -1 }
+      }
+    \int_compare:nNnTF { \l__hook_patch_num_args_int } > { \c_zero_int }
+      {
+        \tl_set:Nx \l__hook_patch_param_text_tl
+          { \bool_if:NTF #1 { [####1] } {  ####1  } }
+        \tl_set:Nx \l__hook_patch_replacement_tl
+          { \bool_if:NTF #1 { [####1] } { {####1} } }
+        \int_step_inline:nnn { 2 } { \l__hook_patch_num_args_int }
+          {
+            \tl_put_right:Nn \l__hook_patch_param_text_tl    { ## ####1 }
+            \tl_put_right:Nn \l__hook_patch_replacement_tl { { ## ####1 } }
+          }
+      }
+      {
+        \tl_clear:N \l__hook_patch_param_text_tl
+        \tl_clear:N \l__hook_patch_replacement_tl
+      }
+    \group_begin:
+      \int_set:Nn \tex_escapechar:D { `\/ }
+      \use:x
+        {
+    \group_end:
+    \tl_set:Nx \exp_not:N \l__hook_patch_prefixes_tl
+      { \exp_not:N \__hook_make_prefixes:w \cs_prefix_spec:N #2 / / }
+        }
+    \use:x
+      {
+        \l__hook_patch_prefixes_tl \tex_def:D
+            \exp_not:N #2 \exp_not:V \l__hook_patch_param_text_tl
+          {
+            \str_if_eq:nnT {#4} { before }
+              { \exp_not:N \UseHook { cmd / #3 / #4 } }
+            \exp_args:No \exp_not:o
+              { \exp_after:wN #2 \l__hook_patch_replacement_tl }
+            \str_if_eq:nnT {#4} { after }
+              { \exp_not:N \UseHook { cmd / #3 / #4 } }
+          }
+      }
+  }
+\cs_new:Npn \__hook_make_prefixes:w / #1 /
+  {
+    \tl_if_empty:nF {#1}
+      {
+        \exp_not:c { tex_ \tl_trim_spaces:n {#1} :D }
+        \__hook_make_prefixes:w /
+      }
+  }
+\cs_new_protected:Npn \__hook_retokenize_patch:Nnn #1 #2 #3
+  {
+    \__hook_patch_debug:x { ..~command~can~only~be~patched~by~rescanning }
+    \str_if_eq:eeTF { \cs_argument_spec:N #1 } { }
+      { \__hook_patch_expand_redefine:NNnn \c_false_bool #1 {#2} {#3} }
+      {
+        \tl_set:Nx \l__hook_tmpa_tl
+          {
+            \int_compare:nNnTF { \char_value_catcode:n {`\@ } } = { 12 }
+              { \exp_not:N \makeatletter } { \exp_not:N \makeatother }
+          }
+        \tl_set:Nx \l__hook_tmpb_tl
+          {
+            \bool_if:NTF \l__kernel_expl_bool
+              { \ExplSyntaxOff } { \ExplSyntaxOn }
+          }
+        \use:x
+          {
+            \exp_not:N \__hook_try_patch_with_catcodes:Nnnnw
+                \exp_not:n { #1 {#2} {#3} }
+              { \prg_do_nothing: }
+              { \exp_not:V \l__hook_tmpa_tl } % @
+              { \exp_not:V \l__hook_tmpb_tl } % _:
+              {
+                \exp_not:V \l__hook_tmpa_tl   % @
+                \exp_not:V \l__hook_tmpb_tl   % _:
+              }
+          }
+              \q_recursion_tail \q_recursion_stop
+          {
+            \__kernel_msg_error:nnxx { hooks } { cant-patch }
+              { \c_backslash_str #2 } { retok }
+          }
+      }
+  }
+\cs_new_protected:Npn \__hook_try_patch_with_catcodes:Nnnnw #1 #2 #3 #4
+  {
+    \quark_if_recursion_tail_stop_do:nn {#4} { \use:n }
+    \__hook_patch_debug:x { ++~trying~to~patch~by~retokenization }
+    \__hook_cmd_if_scanable:NnTF {#1} {#4}
+      {
+        \__hook_patch_debug:x { ++~macro~can~be~retokenized~cleanly }
+        \__hook_patch_debug:x { ==~retokenizing~macro~now }
+        \__hook_patch_retokenize:Nnnn #1 {#2} {#3} {#4}
+        \use_i_delimit_by_q_recursion_stop:nw \use_none:n
+      }
+      {
+        \__hook_patch_debug:x { --~macro~cannot~be~retokenized~cleanly }
+        \__hook_try_patch_with_catcodes:Nnnnw #1 {#2} {#3}
+      }
+  }
+\cs_new_eq:NN \kerneltmpDoNotUse !
+\cs_new_protected:Npn \__hook_patch_required_catcodes:
+  {
+    \char_set_catcode_escape:N \\
+    \char_set_catcode_group_begin:N \{
+    \char_set_catcode_group_end:N \}
+    \char_set_catcode_parameter:N \#
+    % \int_set:Nn \tex_endlinechar:D { -1 }
+    % \int_set:Nn \tex_newlinechar:D { -1 }
+  }
+\prg_new_protected_conditional:Npnn \__hook_cmd_if_scanable:Nn #1 #2 { TF }
+  {
+    \cs_set_eq:NN \kerneltmpDoNotUse \scan_stop:
+    \cs_set_eq:NN \__hook_tmp:w \scan_stop:
+    \use:x
+      {
+        \cs_set:Npn \__hook_tmp:w
+            ####1 \tl_to_str:n { macro: } ####2 -> ####3 \s__hook_mark
+          { ####1 \def \kerneltmpDoNotUse ####2   {####3} }
+        \tl_set:Nx \exp_not:N \l__hook_tmpa_tl
+          { \exp_not:N \__hook_tmp:w \token_to_meaning:N #1 \s__hook_mark }
+      }
+    \tl_rescan:nV { #2 \__hook_patch_required_catcodes: } \l__hook_tmpa_tl
+    \token_if_eq_meaning:NNTF #1 \kerneltmpDoNotUse
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\cs_new_protected:Npn \__hook_patch_retokenize:Nnnn #1 #2 #3 #4
+  {
+    \cs_set_eq:NN \kerneltmpDoNotUse \scan_stop:
+    \cs_set_eq:NN \__hook_tmp:w \scan_stop:
+    \use:x
+      {
+        \cs_set:Npn \__hook_tmp:w
+            ####1 \tl_to_str:n { macro: } ####2 -> ####3 \s__hook_mark
+          {
+            ####1 \def \kerneltmpDoNotUse ####2
+              {
+                \str_if_eq:nnT {#3} { before }
+                  { \token_to_str:N \UseHook { cmd / #2 / #3 } }
+                ####3
+                \str_if_eq:nnT {#3} { after }
+                  { \token_to_str:N \UseHook { cmd / #2 / #3 } }
+              }
+          }
+        \tl_set:Nx \exp_not:N \l__hook_tmpa_tl
+          { \exp_not:N \__hook_tmp:w \token_to_meaning:N #1 \s__hook_mark }
+      }
+    \tl_rescan:nV { #4 \__hook_patch_required_catcodes: } \l__hook_tmpa_tl
+    \cs_set_eq:NN #1 \kerneltmpDoNotUse
+  }
+\__kernel_msg_new:nnnn { hooks } { wrong-cmd-hook }
+  {
+    Command~hook~`cmd/#1/#2'~invalid.\\
+    The~hook~should~be~`cmd/#1/before'~or~`cmd/#1/after'.
+  }
+  {
+    You~tried~to~add~a~hook~to~command~\iow_char:N \\#1,~but~`#2'~
+    is~an~invalid~position.~Only~`before'~or~`after'~are~allowed.
+  }
+\__kernel_msg_new:nnnn { hooks } { cant-patch }
+  {
+    Command~`#1'~cannot~have~hooks~because~it~
+    \__hook_unpatchable_cases:n {#2} .
+  }
+  {
+    You~tried~to~add~a~hook~to~`#1',~but~LaTeX~was~not~able~to~
+    add~the~hook~to~that~command~because~`#1'~
+    \__hook_unpatchable_cases:n {#2} .
+  }
+\cs_new:Npn \__hook_unpatchable_cases:n #1
+  {
+    \str_case:nn {#1}
+      {
+        { undef } { doesn't~exist }
+        { macro } { is~not~a~macro }
+        { expl3 } { is~a~private~expl3~macro }
+        { retok } { can't~be~retokenized~cleanly }
+      }
+  }
+\ExplSyntaxOff
 %%% From File: ltalloc.dtx
 \chardef\@xxxii=32
 \mathchardef\@Mi=10001
@@ -5276,6 +5738,131 @@ Type  H <return>  for immediate help.}%
 \def\@setpar#1{\def\par{#1}\def\@par{#1}}
 \def\@par{\let\par\@@par\par}
 \def\@restorepar{\def\par{\@par}}
+%% File: ltpara.dtx (C) Copyright 2020-2021
+%%% From File: ltpara.dtx
+\def\ltparaversion{v1.0f}
+\def\ltparadate{2021/04/16}
+
+
+\ExplSyntaxOn
+\hook_new_pair:nn{para/before}{para/after}
+\hook_new_pair:nn{para/begin}{para/end}
+\let \@kernel@before@para@before \@empty
+\let \@kernel@before@para@begin  \@empty
+\let \@kernel@after@para@end     \@empty
+\let \@kernel@after@para@after   \@empty
+\tl_new:N \g__para_standard_everypar_tl
+\tl_gset:Nn \g__para_standard_everypar_tl {
+  \box_gset_to_last:N \g_para_indent_box
+  \group_begin:
+    \tex_par:D
+  \group_end:
+  \tex_everypar:D { \__kernel_msg_error:nnnn {para}{mode}{before}{vertical} }
+  \@kernel@before@para@before
+  \hook_use:n {para/before}
+  \group_begin:
+    \tex_everypar:D {}
+    \skip_zero:N \tex_parskip:D
+    \tex_noindent:D
+  \group_end:
+  \tex_everypar:D{\g__para_standard_everypar_tl}
+  \@kernel@before@para@begin
+  \hook_use:n {para/begin}
+  \if_mode_horizontal: \else:
+    \__kernel_msg_error:nnnn {para}{mode}{begin}{vertical} \fi:
+  \__para_handle_indent:
+}
+\tex_everypar:D{\g__para_standard_everypar_tl}
+\newtoks \everypar
+
+\tl_gput_right:Nx \g__para_standard_everypar_tl {
+    \exp_not:N \the
+    \exp_not:N \toks
+    \the \allocationnumber
+    \c_space_tl
+}
+\box_new:N \g_para_indent_box
+
+\cs_new:Npn \__para_handle_indent: {
+  \box_use_drop:N \g_para_indent_box
+}
+\cs_new:Npn \para_omit_indent: {
+  \box_gclear:N \g_para_indent_box
+}
+\cs_set_eq:NN \IndentBox \g_para_indent_box
+\cs_set_eq:NN \OmitIndent \para_omit_indent:
+\cs_new_protected:Npn \para_end: {
+  \mode_if_horizontal:TF {
+    \mode_if_inner:F {
+         \tex_unskip:D
+         \hook_use:n{para/end}
+         \@kernel@after@para@end
+         \mode_if_horizontal:TF {
+           \if_int_compare:w 0 < \tex_lastnodetype:D
+             \tex_kern:D \c_zero_dim
+           \fi:
+           \tex_par:D
+           \hook_use:n{para/after}
+           \@kernel@after@para@after
+         }
+         { \__kernel_msg_error:nnnn {para}{mode}{end}{horizontal} }
+    }
+  }
+  \tex_par:D
+}
+\cs_new:Npn \para_raw_indent: {
+  \mode_if_vertical:TF
+       {
+         \tex_everypar:D {
+           \box_gset_to_last:N \g_para_indent_box
+           \tex_everypar:D { \g__para_standard_everypar_tl }
+           \__para_handle_indent:
+           \the\everypar }
+       }
+       { \__kernel_msg_error:nn {para}{raw} }
+  \tex_indent:D
+}
+\cs_new:Npn \para_raw_noindent: {
+  \mode_if_vertical:TF
+       {
+         \tex_everypar:D {
+           \tex_everypar:D { \g__para_standard_everypar_tl }
+           \the\everypar }
+       }
+       { \__kernel_msg_error:nn {para}{raw} }
+  \tex_noindent:D
+}
+\cs_new_eq:NN \para_raw_end: \tex_par:D
+\cs_set_eq:NN \RawIndent   \para_raw_indent:
+\cs_set_eq:NN \RawNoindent \para_raw_noindent:
+\cs_set_eq:NN \RawParEnd   \para_raw_end:
+\cs_set_eq:NN \par     \para_end:
+\cs_set_eq:NN \@@par   \para_end:
+\cs_set_eq:NN \endgraf \para_end:
+\everypar{\@nodocument} %% To get an error if text appears before the
+\__kernel_msg_new:nnnn {para} {mode}
+  {
+    Illegal~mode~ change~ in~ hook~ 'para/#1'.\\
+    Hook~ code~ did~ not~ remain~ in~ #2~ mode.
+  }
+  {
+    Paragraph~ hooks~ cannot~ change~ the~ TeX~ mode~ without~ causing~
+    endless~ recursion.~ The~ hook~ code~ in~ 'para/#1'~ needs~ to~ stay~
+    in~ #2~ mode,~ but~ it~ didn't.~ Examine~ the~ hook~
+    code~ with~ \ShowHook~ to~ find~ the~ issue.
+  }
+\__kernel_msg_new:nnnn {para} {raw}
+  {
+     Paragraph started while not in vertical mode.
+  }
+  {
+    Starting a paragraph with \RawIndent or \RawNoindent
+    (or \para_raw_indent: or \para_raw_noindent:) is only
+    allowed if LaTeX is in vertical mode.
+  }
+
+\ExplSyntaxOff
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%% From File: ltspace.dtx
 \message{spacing,}
 \DeclareRobustCommand\pagebreak{\@testopt{\@no@pgbk-}4}
@@ -5523,8 +6110,6 @@ Type  H <return>  for immediate help.}%
   \LaTeX\kern.15em2$_{\textstyle\varepsilon}$}}
 %%% From File: ltfiles.dtx
 \message{files,}
-\newread\@inputcheck
-\newwrite\@unused
 \newwrite\@mainaux
 \newwrite\@partaux
 \newif\if@filesw \@fileswtrue
@@ -5597,8 +6182,6 @@ Type  H <return>  for immediate help.}%
   \let\expandafter\noexpand\csname
        __hook env/document/begin\endcsname
   \noexpand\@empty}
-\let \@kernel@before@begindocument \@empty
-\let \@kernel@after@begindocument \@empty
 
 \@onlypreamble\document
 \let\normalsfcodes\@empty
@@ -5726,16 +6309,18 @@ Type  H <return>  for immediate help.}%
   \openin\@inputcheck"#1" %
   \ifeof\@inputcheck
     \ifx\input@path\@undefined
-      \def\reserved@a{#3}%
+      \let\reserved@a\@secondoftwo
     \else
-      \def\reserved@a{\@iffileonpath{#1}{#2}{#3}}%
+      \def\reserved@a{\@iffileonpath{#1}}%
     \fi
   \else
     \closein\@inputcheck
     \edef\@filef@und{"#1" }%
-    \def\reserved@a{#2}%
+    \let\reserved@a\@firstoftwo
   \fi
-  \reserved@a}
+  \expandafter\def\expandafter\reserved@a
+    \expandafter{\reserved@a{#2}{#3}}%
+\reserved@a}
 \long\def\@iffileonpath#1{%
   \let\reserved@a\@secondoftwo
   \expandafter\@tfor\expandafter\reserved@b\expandafter
@@ -6458,7 +7043,9 @@ Type  H <return>  for immediate help.}%
 \DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
    \edef\f@family{#2}%
    \set@target@series{#3}%
-   \edef\f@shape{#4}\selectfont
+   \edef\f@shape{#4}%
+   \let\delayed@f@adjustment\@empty
+   \selectfont
    \ignorespaces}
 \DeclareRobustCommand\linespread[1]
    {\set@fontsize{#1}\f@size\f@baselineskip}
@@ -7402,6 +7989,7 @@ Type  H <return>  for immediate help.}%
       \fi
       \let\delayed@f@adjustment\@empty
     \fi
+    \@forced@seriesfalse
     \xdef\font@name{%
       \csname\curr@fontshape/\f@size\endcsname}%
     \pickup@font
@@ -8832,6 +9420,7 @@ Type  H <return>  for immediate help.}%
    \edef\f@family{\familydefault}%
    \edef\f@series{\seriesdefault}%
    \edef\f@shape{\shapedefault}%
+   \let\delayed@f@adjustment\@empty
    \UseHook{normalfont}%
    \@defaultfamilyhook        % hookname from 2020/02 will vanish
    \selectfont}
@@ -9063,7 +9652,6 @@ Type  H <return>  for immediate help.}%
   \egroup
 }
 \def\textcompsubstdefault{\rmsubstdefault}
-
 \def\DeclareEncodingSubset#1#2{%
   \DeclareEncodingSubset@aux{#1}#2*\DeclareEncodingSubset@aux
 }
@@ -10181,7 +10769,7 @@ Type  H <return>  for immediate help.}%
 }
 \let\@eqnsel=\relax
 \def\nonumber{\global\@eqnswfalse}
-\def\@eqncr{%
+\protected\def\@eqncr{%
    {\ifnum0=`}\fi
    \@ifstar{%
       \global\@eqpen\@M\@yeqncr
@@ -10203,7 +10791,7 @@ Type  H <return>  for immediate help.}%
      \reserved@a \if@eqnsw\@eqnnum\stepcounter{equation}\fi
      \global\@eqnswtrue\global\@eqcnt\z@\cr}
 \let\@seqncr=\@eqncr
-\@namedef{eqnarray*}{\def\@eqncr{\nonumber\@seqncr}\eqnarray}
+\@namedef{eqnarray*}{\protected\def\@eqncr{\nonumber\@seqncr}\eqnarray}
 \@namedef{endeqnarray*}{\nonumber\endeqnarray}
 \def\lefteqn#1{\rlap{$\displaystyle #1$}}
 \DeclareRobustCommand{\ensuremath}{%
@@ -10812,7 +11400,7 @@ Type  H <return>  for immediate help.}%
 \def\@addfield{\global\setbox\@curline\hbox{\unhbox
      \@curline\unhbox\@curfield}}
 \def\@ifatmargin{\ifdim \wd\@curline =\z@}
-\def\@tabcr{\@stopline \@ifstar{\penalty \@M \@xtabcr}\@xtabcr}
+\protected\def\@tabcr{\@stopline \@ifstar{\penalty \@M \@xtabcr}\@xtabcr}
 \def\@xtabcr{\@ifnextchar[\@itabcr{\@startline\ignorespaces}}
 \def\@itabcr[#1]{\@vspace@calcify{#1}\@startline\ignorespaces}
 \def\tabbing{\lineskip \z@skip\let\>\@rtab\let\<\@ltab\let\=\@settab
@@ -10930,14 +11518,14 @@ Type  H <return>  for immediate help.}%
     \lineskip\z@skip\baselineskip\z@skip
     \ifhmode \@preamerr\z@ \@@par\fi
     \@preamble}
-\def\@arraycr{%
+\protected\def\@arraycr{%
   ${\ifnum0=`}\fi\@ifstar\@xarraycr\@xarraycr}
 \def\@xarraycr{\@ifnextchar[\@argarraycr{\ifnum0=`{\fi}${}\cr}}
 \def\@argarraycr[#1]{%
   \ifnum0=`{\fi}${}\ifdim #1>\z@ \@xargarraycr{#1}\else
    \@yargarraycr{#1}\fi}
 \let\tabularnewline\relax
-\def\@tabularcr{%
+\protected\def\@tabularcr{%
   {\ifnum0=`}\fi\@ifstar\@xtabularcr\@xtabularcr}
 \def\@xtabularcr{\@ifnextchar[\@argtabularcr{\ifnum0=`{\fi}\cr}}
 \def\@argtabularcr[#1]{%
@@ -11171,7 +11759,7 @@ Type  H <return>  for immediate help.}%
     \let\\\@stackcr
     \@ishortstack}
 \def\@ishortstack#1{\ialign{\mb@l {##}\unskip\mb@r\cr #1\crcr}\egroup}
-\def\@stackcr{\@ifstar\@ixstackcr\@ixstackcr}
+\protected\def\@stackcr{\@ifstar\@ixstackcr\@ixstackcr}
 \def\@ixstackcr{\@ifnextchar[\@istackcr{\cr\ignorespaces}}
 \def\@istackcr[#1]{\cr\noalign{\@vspace@calcify{#1}}\ignorespaces}
 \newif\if@negarg
@@ -12046,12 +12634,6 @@ Type  H <return>  for immediate help.}%
   \endgroup
   \@footnotemark
 }
-%%<latexrelease>\IncludeInRelease{0000/00/00}%
-%%<latexrelease>                 {\footref}{Add footref}%
-%%<latexrelease>
-%%<latexrelease>\let\footref\@undefined
-%%<latexrelease>
-%%<latexrelease>\EndIncludeInRelease
 %%% From File: ltidxglo.dtx
 \message{index,}
 \def\makeindex{%
@@ -12409,14 +12991,15 @@ Type  H <return>  for immediate help.}%
 \@onlypreamble\@process@ptions
 \def\@xprocess@ptions{%
   \ifx\@currext\@clsextension\else
+   \ifx\@classoptionslist\relax\else
     \@for\CurrentOption:=\@classoptionslist\do{%
       \ifx\CurrentOption\@empty\else
-        \@expandtwoargs\in@{,\CurrentOption,}{,\@declaredoptions,}%
-        \ifin@
+        \@ifundefined{ds@\CurrentOption}{}{%
           \@use@ption
           \expandafter\let\csname ds@\CurrentOption\endcsname\@empty
-        \fi
+        }%
       \fi}%
+    \fi
   \fi
   \@process@pti@ns}
 \@onlypreamble\@xprocess@ptions
@@ -12798,14 +13381,12 @@ Type  H <return>  for immediate help.}%
       \let\write\@gobbletwo%
       \let\closeout\@gobble%
     \else%
-      \edef\reserved@a{#1}%
-      \edef\reserved@a{\detokenize\expandafter{\reserved@a}}%
       \edef\reserved@b{\detokenize\expandafter{\jobname}}%
-      \ifx\reserved@a\reserved@b%
+      \ifx\@curr@file\reserved@b%
         \@fileswtrue%
       \else%
         \edef\reserved@b{\reserved@b\detokenize{.tex}}%
-        \ifx\reserved@a\reserved@b
+        \ifx\@curr@file\reserved@b
           \@fileswtrue%
         \fi%
       \fi%
@@ -13077,8 +13658,8 @@ Type  H <return>  for immediate help.}%
   \fi
 }
 %%% From File: ltfilehook.dtx
-\providecommand\ltfilehookversion{v1.0g}
-\providecommand\ltfilehookdate{2021/02/08}
+\providecommand\ltfilehookversion{v1.0j}
+\providecommand\ltfilehookdate{2021/04/29}
 \ExplSyntaxOn
 \tl_new:N \CurrentFile
 \tl_new:N \CurrentFilePath
@@ -13116,7 +13697,8 @@ Type  H <return>  for immediate help.}%
 \cs_new:Npn \__filehook_drop_extension_aux:nnn #1 #2 #3
    { \tl_if_empty:nF {#1} { #1 / } #2 }
 \tl_new:N \l__filehook_internal_tl
-\seq_new:N \g__filehook_input_file_seq
+\seq_if_exist:NF \g__filehook_input_file_seq
+  { \seq_new:N \g__filehook_input_file_seq }
 \cs_new_protected:Npn \__filehook_file_push:
   {
     \seq_gpush:Nx \g__filehook_input_file_seq
@@ -13130,7 +13712,7 @@ Type  H <return>  for immediate help.}%
     \seq_gpop:NNTF \g__filehook_input_file_seq \l__filehook_internal_tl
       { \exp_after:wN \__filehook_file_pop_assign:nnnn \l__filehook_internal_tl }
       {
-        \msg_error:nnn { hooks } { should-not-happen }
+        \__kernel_msg_error:nnn { hooks } { should-not-happen }
           { Tried~to~pop~from~an~empty~file~name~stack. }
       }
   }
@@ -13218,6 +13800,7 @@ Type  H <return>  for immediate help.}%
   \begingroup
     \escapechar\m@ne
     \let\protect\string
+    \edef~{\string~}%
     \expandafter\def\csname\expandafter\endcsname
       \expandafter{\csname\endcsname}%
     \@expl@@@filehook@if@no@extension@@nTF{#1}%
@@ -13340,7 +13923,7 @@ Type  H <return>  for immediate help.}%
 \cs_new_eq:NN \@expl@@@filehook@drop@extension@@N
               \__filehook_drop_extension:N
 \cs_new_eq:NN \@expl@@@filehook@file@push@@
-               \__filehook_file_push:
+              \__filehook_file_push:
 \cs_new_eq:NN \@expl@@@filehook@file@pop@@
               \__filehook_file_pop:
 \cs_new_eq:NN \@expl@@@filehook@file@pop@assign@@nnnn
@@ -13354,7 +13937,7 @@ Type  H <return>  for immediate help.}%
 %%
 %%% From File: ltshipout.dtx
 \providecommand\ltshipoutversion{v1.0i}
-\providecommand\ltshipoutdate{2021/01/25}
+\providecommand\ltshipoutdate{2021/03/17}
 \ExplSyntaxOn
 \bool_new:N \g__shipout_debug_bool
 \cs_new_eq:NN \__shipout_debug:n  \use_none:n
@@ -14865,6 +15448,33 @@ Type  H <return>  for immediate help.}%
   \countdef\xe@alloc@intercharclass=257
   \xe@alloc@intercharclass=\z@
 \fi
+\ifx\directlua\@undefined
+\else
+  \expanded{%
+    \everyjob{\the\everyjob
+    \noexpand%\directlua
+    \directlua{%
+      local function trace_stack_levels (input_ptr)
+        local tracingstacklevels = tex.count.tracingstacklevels
+        if tex.tracingmacros > 0 or input_ptr < tracingstacklevels then
+          if tracingstacklevels > 0 then
+            if input_ptr < tracingstacklevels then
+              return "\string\n\string~" .. string.rep(".",input_ptr)
+            else
+              return "\string~\string~"
+            end
+          else
+            return "\string\n"
+          end
+        else
+          return ""
+        end
+      end
+      luatexbase.add_to_callback('input_level_string',
+        trace_stack_levels,'tracingstacklevels')
+    }%
+  }}%
+\fi
 \unitlength = 1pt
 \fboxsep = 3pt
 \fboxrule = .4pt
@@ -15175,7 +15785,6 @@ Type  H <return>  for immediate help.}%
 \let\@filelist\@gobble
 \def\@addtofilelist#1{\xdef\@filelist{\@filelist,#1}}%
 \@input{latex2e-first-aid-for-external-files.ltx}
-\@input{ltpara.ltx}
 \makeatother
 \errorstopmode
 \dump
diff --git a/Master/texmf-dist/tex/latex-dev/base/latexrelease.sty b/Master/texmf-dist/tex/latex-dev/base/latexrelease.sty
index 529e3cd6df3..4bdca00b45e 100644
--- a/Master/texmf-dist/tex/latex-dev/base/latexrelease.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/latexrelease.sty
@@ -14,10 +14,12 @@
 %% ltdefns.dtx  (with options: `latexrelease')
 %% ltcmd.dtx  (with options: `latexrelease')
 %% lthooks.dtx  (with options: `latexrelease')
+%% ltcmdhooks.dtx  (with options: `latexrelease')
 %% ltalloc.dtx  (with options: `latexrelease')
 %% ltcntrl.dtx  (with options: `latexrelease')
 %% lterror.dtx  (with options: `latexrelease')
 %% ltpar.dtx  (with options: `latexrelease')
+%% ltpara.dtx  (with options: `latexrelease')
 %% ltspace.dtx  (with options: `latexrelease')
 %% ltlogos.dtx  (with options: `latexrelease')
 %% ltfiles.dtx  (with options: `latexrelease')
@@ -52,6 +54,7 @@
 %% ltoutput.dtx  (with options: `latexrelease')
 %% ltfsscmp.dtx  (with options: `latexrelease')
 %% ltfinal.dtx  (with options: `latexrelease')
+%% latexrelease.dtx  (with options: `latexrelease-finish')
 %% 
 %% This is a generated file.
 %% 
@@ -284,7 +287,7 @@
 }
 %%% From File: ltvers.dtx
 \edef\latexreleaseversion
-   {2021-05-01}
+   {2021-06-01}
 \newif\if@includeinrelease
 \@includeinreleasefalse
 \def\IncludeInRelease#1{%
@@ -293,17 +296,37 @@
                 {There is an \string\EndIncludeRelease\space missing}%
   \@includeinreleasefalse
   \fi
-  \kernel@ifnextchar[%
-  {\@IncludeInRelease{#1}}
-  {\@IncludeInRelease{#1}[#1]}}
+  \ifnum0%
+      \ifx\new@moduledate\@empty\else 1\fi
+      \ifnum \expandafter\@parse@version#1//00\@nil=0 1\fi
+      =11
+    \expandafter\@firstoftwo
+  \else
+    \expandafter\@secondoftwo
+  \fi
+    {\finish@module@release{#1}}%
+    {\kernel@ifnextchar[%
+      {\@IncludeInRelease{#1}}
+      {\@IncludeInRelease{#1}[#1]}}}
+\def\finish@module@release#1#2#3{%
+  \toks@{[#1] #3}%
+  \ifnum\expandafter\@parse@version\new@moduledate//00\@nil
+       >\expandafter\@parse@version\fmtversion//00\@nil
+    \GenericInfo{}{Applying: \the\toks@}%
+  \else
+    \GenericInfo{}{Skipping: \the\toks@}%
+    \expandafter\gobble@finish@module@release
+  \fi}
+\long\def\gobble@finish@module@release#1\EndModuleRelease{%
+  \EndModuleRelease}
 \def\@IncludeInRelease#1[#2]{\@IncludeInRele@se{#2}}
 \def\@IncludeInRele@se#1#2#3{%
   \toks@{[#1] #3}%
   \expandafter\ifx\csname\string#2+\@currname+IIR\endcsname\relax
     \ifnum\expandafter\@parse@version#1//00\@nil
-          >\expandafter\@parse@version\fmtversion//00\@nil
+         >\expandafter\@parse@version\fmtversion//00\@nil
       \GenericInfo{}{Skipping: \the\toks@}%
-     \expandafter\expandafter\expandafter\@gobble@IncludeInRelease
+      \expandafter\expandafter\expandafter\@gobble@IncludeInRelease
     \else
       \GenericInfo{}{Applying: \the\toks@}%
       \@includeinreleasetrue
@@ -319,6 +342,9 @@
   \@includeinreleasefalse
 \else
   \PackageError{latexrelease}{mis-matched EndIncludeInRelease}{}%
+\fi
+\if@skipping@module
+  \expandafter\new@module@skip
 \fi}
 \long\def\@gobble@IncludeInRelease#1\EndIncludeInRelease{%
   \@includeinreleasefalse
@@ -328,13 +354,55 @@
                                    #2#3\@end@check@IncludeInRelease{%
   \ifx\@check@IncludeInRelease#2\else
     \PackageError{latexrelease}{skipped IncludeInRelease for tag \string#2}{}%
+  \fi
+  \if@skipping@module
+    \expandafter\new@module@skip
+  \fi}
+\let\if@skipping@module\iffalse
+\def\@skipping@moduletrue{\let\if@skipping@module\iftrue}
+\def\@skipping@modulefalse{\let\if@skipping@module\iffalse}
+\let\new@modulename\@empty
+\let\new@moduledate\@empty
+\def\NewModuleRelease#1#2#3{%
+  \ifx\new@modulename\@empty \else
+    \@latex@error{Nested \noexpand\NewModuleRelease forbidden.}\@ehd \fi
+  \edef\new@moduledate{#1}%
+  \edef\new@modulename{#2}%
+  \GenericInfo{}{BEGIN module: \new@modulename\space (\new@moduledate)}%
+  \GenericInfo{}{ \@spaces\@spaces\@spaces\space#3\@gobble}%
+  \ifnum\sourceLaTeXdate<%
+      \expandafter\@parse@version\new@moduledate//00\@nil\relax
+    \ifnum\expandafter\@parse@version\fmtversion//00\@nil<%
+          \expandafter\@parse@version\new@moduledate//00\@nil\relax
+      \GenericInfo{}{Skipping module \new@modulename}%
+      \expandafter\expandafter
+      \expandafter\gobble@finish@module@release
+    \else
+      \GenericInfo{}{Applying module \new@modulename}
+      \@skipping@modulefalse
+    \fi
+  \else
+    \GenericInfo{}{Skipping module \new@modulename}
+    \@skipping@moduletrue
+    \expandafter\new@module@skip
+  \fi}
+\long\def\new@module@skip#1\IncludeInRelease{\IncludeInRelease}
+\def\EndModuleRelease{%
+  \ifx\new@modulename\@empty
+    \@latex@error{Extra \string\EndModuleRelease.}\@eha
+  \else
+    \GenericInfo{}{END module: \new@modulename\space (\new@moduledate)}%
+    \let\new@modulename\@empty
+    \let\new@moduledate\@empty
+    \@skipping@modulefalse
   \fi}
 \ProvidesPackage{latexrelease}
-          [2021/01/23 v1.0l LaTeX release emulation and tests
+          [2021/04/29 v1.0n LaTeX release emulation and tests
               (including releases up to \latexreleaseversion)]
 \NeedsTeXFormat{LaTeX2e}[1996/06/01]
-\edef\sourceLaTeXdate{%
-  \expandafter\@parse@version\fmtversion//00\@nil}
+\@ifundefined{sourceLaTeXdate}{%
+  \edef\sourceLaTeXdate{%
+    \expandafter\@parse@version\fmtversion//00\@nil}}{}%
 \DeclareOption*{%
   \def\@IncludeInRelease#1[#2]{\@IncludeInRele@se{#1}}%
   \let\requestedpatchdate\CurrentOption}
@@ -385,6 +453,76 @@ of this package available from CTAN}
 \fi
 \let\fmtversion\requestedpatchdate
 \let\currentLaTeXdate\requestedLaTeXdate
+\csname ExplSyntaxOn\endcsname
+\csname ExplSyntaxOff\endcsname
+\begingroup
+  \endlinechar=-1
+  \catcode95=11 % _
+  \catcode58=11 % :
+  \catcode126=10 % ~
+  \catcode32=09 % <space>
+  \xdef\latexrelease@postexpl{\unexpanded{%
+\cs_gset_protected:Npn \__latexrelease_declare_command:w
+  { \@star@or@long \__latexrelease_declare_command:Nw }
+\cs_gset_protected:Npn \__latexrelease_declare_command:Nw #1
+  { \cs_if_exist:NTF #1 { \renew@command } { \new@command } #1 }
+\cs_gset_protected:Npn \__latexrelease_e@alloc:NnnnnN #1 #2 #3 #4 #5 #6
+  {
+    \cs_if_free:NTF #6
+      { \use:n }
+      {
+        \exp_after:wN \__latexrelease_e@alloc:N
+          \token_to_meaning:N #6 \scan_stop: {#2} #6
+      }
+        { \__latexrelease_e@alloc #1 {#2} {#3} {#4} {#5} #6 }
+  }
+\cs_gset_protected:Npn \__latexrelease_e@alloc:N #1
+  {
+    \if_int_compare:w 0 < 0
+        \if_int_compare:w 10 < 9#1 ~ 1 \fi:
+        \if_charcode:w " #1 1 \fi: \exp_stop_f:
+      \tex_afterassignment:D \__latexrelease_e@alloc:w
+      \@tempcnta #1
+      \use_i:nnn
+    \fi:
+    \use:n
+      {
+        \if_meaning:w \scan_stop: #1
+          \exp_after:wN \use_iv:nnnn
+        \fi:
+        \__latexrelease_e@alloc:N
+      }
+  }
+\cs_gset_protected:Npn \__latexrelease_e@alloc:w #1 \scan_stop: #2 #3
+  {
+    #2 \__latexrelease_tmp:w = \@tempcnta
+    \token_if_eq_meaning:NNTF #3 \__latexrelease_tmp:w
+      { \int_set_eq:NN \allocationnumber \@tempcnta  \use_none:n }
+      { \cs_set_eq:NN #3 \tex_undefined:D            \use:n      }
+  }
+\tl_clear_new:N \l__latexrelease_restores_tl
+\cs_gset:Npn \__latexrelease_tmp:w #1 #2
+  {
+    \quark_if_recursion_tail_stop_do:Nn #1
+      { \cs_undefine:N \__latexrelease_tmp:w }
+    \tl_put_right:Nn \l__latexrelease_restores_tl {#1}
+    \cs_set_eq:cN { __latexrelease_ \cs_to_str:N #1 } #1
+    \cs_set_eq:NN #1 #2
+    \__latexrelease_tmp:w
+  }
+\__latexrelease_tmp:w
+  \__kernel_chk_if_free_cs:N \use_none:n
+  \e@alloc \__latexrelease_e@alloc:NnnnnN
+  \__kernel_msg_error:nnx \use_none:nnn
+  \msg_new:nnnn \msg_gset:nnnn
+  \NewDocumentCommand \DeclareDocumentCommand
+  \newcommand \__latexrelease_declare_command:w
+  \__kernel_msg_error:nnn  \use_none:nnn  % needed while redirect for kernel msgs doesn't work
+  \q_recursion_tail \q_recursion_tail
+  \q_recursion_stop
+\msg_redirect_name:nnn { hooks } { exists } { none }
+  }}%
+\endgroup
 %%% From File: ltdirchk.dtx
 \ifx\directlua\undefined\else
 \IncludeInRelease{2015/10/01}{\luatexluafunction}
@@ -682,6 +820,45 @@ of this package available from CTAN}
   \global\chardef#1\allocationnumber
   \wlog{\string#1=\string\insert\the\allocationnumber}}
 \EndIncludeInRelease
+\IncludeInRelease{2021/06/01}{\tracingstacklevels}%
+                 {tracingstacklevels}%
+\ifx\directlua\@undefined
+  % \tracingstacklevels=0 % added in 2021
+\else
+  \newcount\tracingstacklevels
+  % Code for \tracingstacklevels defined in ltfinal.dtx
+\fi
+\EndIncludeInRelease
+
+\IncludeInRelease{0000/00/00}{\tracingstacklevels}%
+                 {tracingstacklevels}%
+\ifx\directlua\@undefined
+\else
+  \let\tracingstacklevels\@undefined
+\fi
+\EndIncludeInRelease
+\IncludeInRelease{2021/06/01}{\loggingall}
+                 {\tracingstacklevels and \tracinglostchars=3}%
+\edef\loggingall{%
+  \tracingstats\tw@
+  \tracingpages\@ne
+  \tracinglostchars\thr@@
+  \tracingparagraphs\@ne
+  \tracinggroups\@ne
+  \tracingifs\@ne
+  \tracingscantokens\@ne
+  \tracingnesting\@ne
+  \errorcontextlines\maxdimen
+  \ifdefined\tracingstacklevels \tracingstacklevels\maxdimen \fi
+  \noexpand \loggingoutput
+  \tracingmacros\tw@
+  \tracingcommands\thr@@
+  \tracingrestores\@ne
+  \tracingassigns\@ne
+}%
+\def\tracingall{\showoverfull\loggingall}
+\EndIncludeInRelease
+
 \IncludeInRelease{2015/01/01}{\loggingall}{etex tracing}%
 \ifx\tracingscantokens\@undefined
 \gdef\loggingall{%
@@ -715,6 +892,7 @@ of this package available from CTAN}
 \fi
 \gdef\tracingall{\showoverfull\loggingall}
 \EndIncludeInRelease
+
 \IncludeInRelease{0000/00/00}{\loggingall}{etex tracing}%
 \gdef\loggingall{\tracingcommands\tw@\tracingstats\tw@
   \tracingpages\@ne\tracinglostchars\@ne
@@ -724,6 +902,30 @@ of this package available from CTAN}
 \EndIncludeInRelease
 \IncludeInRelease{2015/01/01}{\tracingnone}%
                              {turn off etex tracing}%
+\edef\tracingnone{%
+  \tracingassigns\z@
+  \tracingrestores\z@
+  \tracingonline\z@
+  \tracingcommands\z@
+  \showboxdepth\m@ne
+  \showboxbreadth\m@ne
+  \tracingoutput\z@
+  \errorcontextlines\m@ne
+  \ifdefined\tracingstacklevels \tracingstacklevels\z@ \fi
+  \tracingnesting\z@
+  \tracingscantokens\z@
+  \tracingifs\z@
+  \tracinggroups\z@
+  \tracingparagraphs\z@
+  \tracingmacros\z@
+  \tracinglostchars\@ne
+  \tracingpages\z@
+  \tracingstats\z@
+}%
+\EndIncludeInRelease
+
+\IncludeInRelease{2015/01/01}{\tracingnone}%
+                             {turn off etex tracing}%
 \ifx\tracingscantokens\@undefined
 \def\tracingnone{%
   \tracingonline\z@
@@ -760,6 +962,14 @@ of this package available from CTAN}
   \tracingstats\z@
 }%
 \fi
+\EndIncludeInRelease
+
+\IncludeInRelease{0000/00/00}{\tracingnone}%
+                             {turn off etex tracing}%
+\let\tracingnone\@undefined
+\EndIncludeInRelease
+\IncludeInRelease{2015/01/01}{\hideoutput}%
+                             {hide output from tracing}%
 \def\hideoutput{%
   \tracingoutput\z@
   \showboxbreadth\m@ne
@@ -767,9 +977,9 @@ of this package available from CTAN}
   \tracingonline\m@ne
 }%
 \EndIncludeInRelease
-\IncludeInRelease{0000/00/00}{\tracingnone}%
-                             {turn off etex tracing}%
-\let\tracingnone\@undefined
+
+\IncludeInRelease{0000/00/00}{\hideoutput}%
+                             {hide output from tracing}%
 \let\hideoutput\@undefined
 \EndIncludeInRelease
 \ifx\directlua\@undefined\else
@@ -983,14 +1193,20 @@ of this package available from CTAN}
 \fi
 %%% From File: ltexpl.dtx
 \IncludeInRelease{2020/10/01}%
-  {kernel@enddocument hooks}{Define kernel enddocument Hooks}%
-\let\@kernel@after@enddocument\@empty
-\let\@kernel@after@enddocument@afterlastpage\@empty
+  {kernel@enddocument hooks}{Define several kernel hooks}
+\ifx\@kernel@after@enddocument\@undefined
+  \let \@kernel@after@enddocument               \@empty
+  \let \@kernel@after@enddocument@afterlastpage \@empty
+  \let \@kernel@before@begindocument \@empty
+  \let \@kernel@after@begindocument  \@empty
+\fi
 \EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
-  {kernel@enddocument hooks}{Define kernel enddocument Hooks}%
+  {kernel@enddocument hooks}{Define several kernel hooks}
 \let\@kernel@after@enddocument\@undefined
 \let\@kernel@after@enddocument@afterlastpage\@undefined
+\let\@kernel@before@begindocument\@undefined
+\let\@kernel@after@begindocument\@undefined
 \EndIncludeInRelease
 \IncludeInRelease{2020/10/01}%
             {\@expl@sys@load@backend@@}{Roll forward support}%
@@ -1565,13 +1781,13 @@ of this package available from CTAN}
 
 \EndIncludeInRelease
 %%% From File: ltcmd.dtx
-\def\ltcmdversion{v1.0a}
-\def\ltcmddate{2021/01/21}
+\def\ltcmdversion{v1.0d}
+\def\ltcmddate{2021-04-19}
 \edef\@latexrelease@catcode@null{\the\catcode`\^^@ }
 \catcode`\^^@=12
-\IncludeInRelease{2021/05/01}%
-                 {\NewDocumentCommand}{Document commands}%
 \ExplSyntaxOn
+\NewModuleRelease{2020/10/01}{ltcmd}
+                 {Document~command~parser}%
 \tl_new:N \l__cmd_arg_spec_tl
 \tl_new:N \l__cmd_args_tl
 \tl_new:N \l__cmd_args_i_tl
@@ -3275,7 +3491,7 @@ of this package available from CTAN}
   }
 \cs_new_protected:Npn \__cmd_get_arg_spec:NTF #1#2#3
   {
-    \__cmd_cmd_if_xparse:NTF #1
+    \__kernel_cmd_if_xparse:NTF #1
       {
         \tl_set:Nx \ArgumentSpecification { \tl_item:Nn #1 { 2 } }
         #2
@@ -3377,7 +3593,7 @@ of this package available from CTAN}
     #1 {#2} {#4}
     \__cmd_tl_mapthread_loop:w #1#3 \q_mark
   }
-\cs_new_protected:Npn \__cmd_cmd_if_xparse:NTF #1
+\cs_new_protected:Npn \__kernel_cmd_if_xparse:NTF #1
   {
     \exp_args:Nf \str_case_e:nnTF
       {
@@ -3830,31 +4046,21 @@ of this package available from CTAN}
 \cs_new_eq:NN \ShowDocumentEnvironmentArgSpec \__cmd_show_arg_spec:n
 \cs_gset_eq:NN \__kernel_chk_if_free_cs:N \__cmd_chk_if_free_cs:N
 \cs_undefine:N \__cmd_chk_if_free_cs:N
-\ExplSyntaxOff
-\EndIncludeInRelease
-\catcode`\^^@=\@latexrelease@catcode@null\relax
 
-\IncludeInRelease{2020/10/01}%
-                 {\NewDocumentCommand}{Document commands}%
-\@ifundefined{NewDocumentCommand}
-  {%
-    \IfFileExists{xparse.ltx}
-      {\input xparse.ltx }
-      {\@latex@error{LaTeX requires xparse}\@ehd}%
-  }
-  {}
-\EndIncludeInRelease
+\IncludeInRelease{0000/00/00}{ltcmd}%
+                 {Document~command~parser}%
 
-\IncludeInRelease{0000/00/00}%
-                 {\NewDocumentCommand}{Document commands}%
-
-\EndIncludeInRelease
+\EndModuleRelease
+\ExplSyntaxOff
+\@ifundefined{ExplSyntaxOff}{}{\latexrelease@postexpl}
+\catcode`\^^@=\@latexrelease@catcode@null\relax
 %%% From File: lthooks.dtx
-\def\lthooksversion{v1.0h}
-\def\lthooksdate{2021/01/15}
-\IncludeInRelease{2020/10/01}%
-                 {\NewHook}{The hook management}%
+\def\lthooksversion{v1.0m}
+\def\lthooksdate{2021/04/29}
+
 \ExplSyntaxOn
+\NewModuleRelease{2020/10/01}{lthooks}
+                 {The~hook~management~system}
 \bool_new:N \g__hook_debug_bool
 \cs_new_eq:NN \__hook_debug:n \use_none:n
 \cs_new_protected:Npn \hook_debug_on:
@@ -3918,24 +4124,34 @@ of this package available from CTAN}
 \cs_new_protected:Npn \__hook_tl_gclear:N #1
   { \__hook_tl_gset_eq:NN #1 \c_empty_tl }
 \cs_generate_variant:Nn \__hook_tl_gclear:N { c }
+
+
 \cs_new_protected:Npn \hook_new:n #1
   { \__hook_normalize_hook_args:Nn \__hook_new:n {#1} }
 \cs_new_protected:Npn \__hook_new:n #1
   {
-    \hook_if_exist:nTF {#1}
-      { \msg_error:nnn { hooks } { exists } {#1} }
+    \__hook_if_declared:nTF {#1}
+      { \__kernel_msg_error:nnn { hooks } { exists } {#1} }
+      {
+        \tl_new:c { g__hook_#1_declared_tl }
+        \__hook_make_usable:n {#1}
+      }
+  }
+\cs_new_protected:Npn \__hook_make_usable:n #1
+  {
+    \tl_if_exist:cF { __hook~#1 }
       {
         \seq_gput_right:Nn \g__hook_all_seq {#1}
         \tl_new:c { __hook~#1 }
-        \__hook_declare:n {#1}
-        \clist_new:c {g__hook_#1_labels_clist}
+        \__hook_init_structure:n {#1}
+        \clist_new:c { g__hook_#1_labels_clist }
         \tl_new:c { g__hook_#1_reversed_tl }
         \__hook_include_legacy_code_chunk:n {#1}
-     }
+      }
   }
-\cs_new_protected:Npn \__hook_declare:n #1
+\cs_new_protected:Npn \__hook_init_structure:n #1
   {
-    \__hook_if_exist:nF {#1}
+    \__hook_if_structure_exist:nF {#1}
       {
         \prop_new:c { g__hook_#1_code_prop }
         \tl_new:c { __hook_toplevel~#1 }
@@ -3963,6 +4179,64 @@ of this package available from CTAN}
           }
       }
   }
+\IncludeInRelease{2021/06/01}%
+         {\hook_disable:n}{Disable~hooks}
+\cs_new_protected:Npn \hook_disable:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_disable:n {#1} }
+\cs_new_protected:Npn \__hook_disable:n #1
+  {
+    \tl_gclear_new:c { g__hook_#1_declared_tl }
+    \cs_undefine:c { __hook~#1 }
+  }
+\prg_new_conditional:Npnn \__hook_if_disabled:n #1 { p, T, F, TF }
+  {
+    \bool_lazy_and:nnTF
+        { \tl_if_exist_p:c { g__hook_#1_declared_tl } }
+        { ! \tl_if_exist_p:c { __hook~#1 } }
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\EndIncludeInRelease
+\IncludeInRelease{2020/10/01}
+                 {\hook_disable:n}{Disable~hooks}
+
+\cs_new_protected:Npn \hook_disable:n #1 {}
+
+\EndIncludeInRelease
+\IncludeInRelease{2021/06/01}%
+         {\hook_provide:n}{Providing~hooks}
+\cs_new_protected:Npn \hook_provide:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_provide:nn {#1} {   } }
+\cs_new_protected:Npn \hook_provide_reversed:n #1
+  { \__hook_normalize_hook_args:Nn \__hook_provide:nn {#1} { - } }
+\cs_new_protected:Npn \__hook_provide:nn #1 #2
+  {
+    \__hook_if_disabled:nTF {#1}
+      { \__kernel_msg_warning:nnn { hooks } { provide-disabled } {#1} }
+      {
+        \__hook_if_declared:nTF {#1}
+          {
+            \str_if_eq:eeF { \tl_use:c { g__hook_#1_reversed_tl } } {#2}
+              { \__kernel_msg_error:nnn { hooks } { provide-error } {#1} }
+          }
+          {
+            \tl_new:c { g__hook_#1_declared_tl }
+            \__hook_make_usable:n {#1}
+            \tl_gset:cn { g__hook_#1_reversed_tl } {#2}
+          }
+      }
+  }
+\cs_new_protected:Npn \hook_provide_pair:nn #1#2
+  { \hook_provide:n {#1} \hook_provide_reversed:n {#2} }
+\EndIncludeInRelease
+\IncludeInRelease{2020/10/01}
+                 {\hook_provide:n}{Providing~hooks}
+
+\cs_new_protected:Npn \hook_provide_reversed:n #1 {}
+\cs_new_protected:Npn \hook_provide:n #1 {}
+\cs_new_protected:Npn \hook_provide_pair:nn #1#2 {}
+
+\EndIncludeInRelease
 \cs_new:Npn \__hook_parse_label_default:n #1
   {
     \tl_if_novalue:nTF {#1}
@@ -3973,7 +4247,7 @@ of this package available from CTAN}
   {
     \tl_if_empty:nTF {#1}
       {
-        \msg_expandable_error:nn { hooks } { empty-label }
+        \__kernel_msg_expandable_error:nn { hooks } { empty-label }
         \__hook_currname_or_default:
       }
       {
@@ -4001,7 +4275,7 @@ of this package available from CTAN}
       {
         \tl_if_empty:NTF \@currname
           {
-            \msg_expandable_error:nnn { hooks } { should-not-happen }
+            \__kernel_msg_expandable_error:nnn { hooks } { should-not-happen }
               { Empty~default~label. }
             \__hook_make_name:n { label-missing }
           }
@@ -4058,12 +4332,16 @@ of this package available from CTAN}
         \__hook_if_marked_removal:nnTF {#1} {#2}
           { \__hook_unmark_removal:nn {#1} {#2} }
           {
-            \hook_if_exist:nTF {#1}
+            \__hook_if_usable:nTF {#1}
               {
                 \__hook_hook_gput_code_do:nnn {#1} {#2} {#3}
                 \__hook_update_hook_code:n {#1}
               }
-              { \__hook_try_declaring_generic_hook:nnn {#1} {#2} {#3} }
+              {
+                \__hook_if_disabled:nTF {#1}
+                  { \__kernel_msg_error:nnn { hooks } { hook-disabled } {#1} }
+                  { \__hook_try_declaring_generic_hook:nnn {#1} {#2} {#3} }
+              }
           }
       }
   }
@@ -4071,17 +4349,17 @@ of this package available from CTAN}
 \cs_new_protected:Npn \__hook_hook_gput_code_do:nnn #1 #2 #3
   {
     \__hook_debug:n{\iow_term:x{****~ Add~ to~
-                      \hook_if_exist:nF {#1} { undeclared~ }
+                      \__hook_if_usable:nF {#1} { undeclared~ }
                       hook~ #1~ (#2)
                       \on@line\space <-~ \tl_to_str:n{#3}} }
     \str_if_eq:nnTF {#2} { top-level }
       {
         \str_if_eq:eeTF { top-level } { \__hook_currname_or_default: }
           {
-            \__hook_declare:n {#1}
+            \__hook_init_structure:n {#1}
             \__hook_tl_gput_right:cn { __hook_toplevel~#1 } {#3}
           }
-          { \msg_error:nnn { hooks } { misused-top-level } {#1} }
+          { \__kernel_msg_error:nnn { hooks } { misused-top-level } {#1} }
       }
       {
         \prop_get:cnNTF { g__hook_#1_code_prop } {#2} \l__hook_return_tl
@@ -4094,7 +4372,7 @@ of this package available from CTAN}
   }
 \cs_new_protected:Npn \__hook_gput_undeclared_hook:nnn #1 #2 #3
   {
-    \__hook_declare:n {#1}
+    \__hook_init_structure:n {#1}
     \__hook_hook_gput_code_do:nnn {#1} {#2} {#3}
   }
 \cs_new_protected:Npn \__hook_try_declaring_generic_hook:nnn #1
@@ -4122,6 +4400,8 @@ of this package available from CTAN}
       { #2 }
       { #3 } {#1}
   }
+\IncludeInRelease{2021/06/01}%
+         {\__hook_try_declaring_generic_hook:wn}{Support~cmd~hooks}
 \prg_new_protected_conditional:Npnn \__hook_try_declaring_generic_hook:wn
     #1 / #2 / #3 / #4 \scan_stop: #5 { TF }
   {
@@ -4130,7 +4410,12 @@ of this package available from CTAN}
       {
         \prop_if_in:NnTF \c__hook_generics_prop {#1}
           {
-            \hook_if_exist:nF {#5} { \hook_new:n {#5} }
+            \__hook_if_usable:nF {#5}
+              {
+                \str_if_eq:nnT {#1} { cmd }
+                  { \__hook_try_put_cmd_hook:n {#5} }
+                \__hook_make_usable:n {#5}
+              }
             \prop_if_in:NnTF \c__hook_generics_reversed_ii_prop {#2}
               { \tl_gset:cn { g__hook_#5_reversed_tl } { - } }
               {
@@ -4142,6 +4427,32 @@ of this package available from CTAN}
           { \prg_return_false: }
       }
   }
+\EndIncludeInRelease
+\IncludeInRelease{2020/10/01}%
+         {\__hook_try_declaring_generic_hook:wn}{Support~cmd~hooks}
+
+\prg_new_protected_conditional:Npnn \__hook_try_declaring_generic_hook:wn
+    #1 / #2 / #3 / #4 \scan_stop: #5 { TF }
+  {
+    \tl_if_empty:nTF {#2}
+      { \prg_return_false: }
+      {
+        \prop_if_in:NnTF \c__hook_generics_prop {#1}
+          {
+            \__hook_if_declared:nF {#5} { \hook_new:n {#5} }
+            \prop_if_in:NnTF \c__hook_generics_reversed_ii_prop {#2}
+              { \tl_gset:cn { g__hook_#5_reversed_tl } { - } }
+              {
+                \prop_if_in:NnT \c__hook_generics_reversed_iii_prop {#3}
+                  { \tl_gset:cn { g__hook_#5_reversed_tl } { - } }
+              }
+            \prg_return_true:
+          }
+          { \prg_return_false: }
+      }
+  }
+
+\EndIncludeInRelease
 \prg_new_conditional:Npnn \__hook_if_file_hook:w
     #1 / #2 / #3 \s__hook_mark { TF }
   {
@@ -4170,7 +4481,7 @@ of this package available from CTAN}
       { \__hook_strip_double_slash:w #1/#2/#3 / #4 \s__hook_mark }
   }
 \prop_const_from_keyval:Nn \c__hook_generics_prop
-  {env=,file=,package=,class=,include=}
+     {cmd=,env=,file=,package=,class=,include=}
 \prop_const_from_keyval:Nn \c__hook_generics_reversed_ii_prop {after=,end=}
 \prop_const_from_keyval:Nn \c__hook_generics_reversed_iii_prop {after=}
 \prop_const_from_keyval:Nn \c__hook_generics_file_prop {before=,after=}
@@ -4178,7 +4489,7 @@ of this package available from CTAN}
   { \__hook_normalize_hook_args:Nnn \__hook_gremove_code:nn {#1} {#2} }
 \cs_new_protected:Npn \__hook_gremove_code:nn #1 #2
   {
-    \__hook_if_exist:nTF {#1}
+    \__hook_if_structure_exist:nTF {#1}
       {
         \str_if_eq:nnTF {#2} {*}
           {
@@ -4196,7 +4507,7 @@ of this package available from CTAN}
                       {#1} {#2}
               }
           }
-        \hook_if_exist:nT {#1}
+        \__hook_if_usable:nT {#1}
           { \__hook_update_hook_code:n {#1} }
       }
       { \__hook_mark_removal:nn {#1} {#2} }
@@ -4231,14 +4542,14 @@ of this package available from CTAN}
   }
 \cs_new_protected:Npn \__hook_gset_rule:nnnn #1#2#3#4
   {
-    \__hook_declare:n {#1}
+    \__hook_init_structure:n {#1}
     \__hook_rule_gclear:nnn {#1} {#2} {#4}
     \cs_if_exist_use:cTF { __hook_rule_#3_gset:nnn }
       {
           {#1} {#2} {#4}
         \__hook_update_hook_code:n {#1}
       }
-      { \msg_error:nnnnnn { hooks } { unknown-rule }
+      { \__kernel_msg_error:nnnnnn { hooks } { unknown-rule }
                           {#1} {#2} {#3} {#4}        }
   }
 \cs_new_protected:Npn \__hook_rule_before_gset:nnn #1#2#3
@@ -4279,7 +4590,7 @@ of this package available from CTAN}
   {
     \if_int_compare:w \__hook_str_compare:nn {#1} {#2} > 0 \exp_stop_f:
       \prg_return_true:
-    \else
+    \else:
       \prg_return_false:
     \fi:
   }
@@ -4313,7 +4624,7 @@ of this package available from CTAN}
     \__hook_debug:n{ \iow_term:x{^^JUpdate~ code~ for~ hook~
                                     '#1' \on@line :^^J} }
     \__hook_include_legacy_code_chunk:n {#1}
-    \hook_if_exist:nT {#1}
+    \__hook_if_usable:nT {#1}
       {
         \prop_if_empty:cTF {g__hook_#1_code_prop}
           {
@@ -4457,7 +4768,7 @@ of this package available from CTAN}
 \cs_new_protected:cpn { __hook_apply_rule_xE:nnn } #1#2#3
   {
     \__hook_debug:n { \__hook_msg_pair_found:nnn {#1} {#2} {#3} }
-    \msg_error:nnnnnn { hooks } { labels-incompatible }
+    \__kernel_msg_error:nnnnnn { hooks } { labels-incompatible }
       {#1} {#2} {#3} { 1 }
     \use:c { __hook_apply_rule_->:nnn } {#1} {#2} {#3}
     \use:c { __hook_apply_rule_<-:nnn } {#1} {#2} {#3}
@@ -4465,7 +4776,7 @@ of this package available from CTAN}
 \cs_new_protected:cpn { __hook_apply_rule_xW:nnn } #1#2#3
   {
     \__hook_debug:n { \__hook_msg_pair_found:nnn {#1} {#2} {#3} }
-    \msg_warning:nnnnnn { hooks } { labels-incompatible }
+    \__kernel_msg_warning:nnnnnn { hooks } { labels-incompatible }
       {#1} {#2} {#3} { 0 }
   }
 \cs_new_protected:cpn { __hook_apply_rule_->:nnn } #1#2#3
@@ -4533,8 +4844,10 @@ of this package available from CTAN}
   {
     \__hook_preamble_hook:n {#1}
     \__hook_log_cmd:x { ^^J ->~The~hook~'#1': }
-    \hook_if_exist:nF {#1}
-      { \__hook_log_line:x { is~not~declared! } }
+    \__hook_if_usable:nF {#1}
+      { \__hook_log_line:x { The~hook~is~not~declared. } }
+    \__hook_if_disabled:nT {#1}
+      { \__hook_log_line:x { The~hook~is~disabled. } }
     \hook_if_empty:nTF {#1}
       { #2 { The~hook~is~empty } }
       {
@@ -4548,7 +4861,7 @@ of this package available from CTAN}
         \__hook_log_line:x
           {
             Document-level~(top-level)~code
-            \hook_if_exist:nT {#1}
+            \__hook_if_usable:nT {#1}
               { ~(executed~\__hook_if_reversed:nTF {#1} {first} {last} ) } :
           }
         \__hook_log_line_indent:x
@@ -4579,7 +4892,7 @@ of this package available from CTAN}
         \bool_if:NT \l__hook_tmpa_bool
           { \__hook_log_line_indent:x { --- } }
         \bool_lazy_and:nnTF
-            { \hook_if_exist_p:n {#1} }
+            { \__hook_if_usable_p:n {#1} }
             { ! \hook_if_empty_p:n {#1} }
           {
             \__hook_log_line:x
@@ -4601,10 +4914,12 @@ of this package available from CTAN}
               }
           }
           {
+            \__hook_log_line:x { Execution~order: }
             #2
               {
-                Hook~ \hook_if_exist:nTF {#1}
-                  {code~pool~empty} {not~declared}
+                \@spaces Not~set~because~the~hook~ \__hook_if_usable:nTF {#1}
+                  { code~pool~is~empty }
+                  { is~\__hook_if_disabled:nTF {#1} {disabled} {undeclared} }
               }
           }
       }
@@ -4660,10 +4975,14 @@ of this package available from CTAN}
   { \__hook_normalize_hook_args:Nn \__hook_gput_next_code:nn {#1} }
 \cs_new_protected:Npn \__hook_gput_next_code:nn #1 #2
   {
-    \__hook_declare:n {#1}
-    \hook_if_exist:nTF {#1}
-      { \__hook_gput_next_do:nn {#1} {#2} }
-      { \__hook_try_declaring_generic_next_hook:nn {#1} {#2} }
+    \__hook_if_disabled:nTF {#1}
+      { \__kernel_msg_error:nnn { hooks } { hook-disabled } {#1} }
+      {
+        \__hook_init_structure:n {#1}
+        \__hook_if_usable:nTF {#1}
+          { \__hook_gput_next_do:nn {#1} {#2} }
+          { \__hook_try_declaring_generic_next_hook:nn {#1} {#2} }
+      }
   }
 \cs_new_protected:Npn \__hook_gput_next_do:nn #1
   {
@@ -4715,12 +5034,12 @@ of this package available from CTAN}
   {
     \__hook_if_file_hook:wTF #1 / / \s__hook_mark
       {
-        \exp_args:Ne \__hook_if_exist_use:n
+        \exp_args:Ne \__hook_if_usable_use:n
           { \exp_args:Ne \__hook_file_hook_normalize:n {#1} }
       }
-      { \__hook_if_exist_use:n {#1} } % file/ generic hook (e.g. file/before)
+      { \__hook_if_usable_use:n {#1} } % file/ generic hook (e.g. file/before)
   }
-\cs_new_protected:Npn \__hook_if_exist_use:n #1
+\cs_new_protected:Npn \__hook_if_usable_use:n #1
   {
     \tl_if_exist:cT { __hook~#1 }
       {
@@ -4740,9 +5059,10 @@ of this package available from CTAN}
   }
 \cs_new_protected:Npn \__hook_use_once_store:n #1
   { \prop_gput:Nnn \g__hook_execute_immediately_prop {#1} { } }
+
 \prg_new_conditional:Npnn \hook_if_empty:n #1 { p , T , F , TF }
   {
-    \__hook_if_exist:nTF {#1}
+    \__hook_if_structure_exist:nTF {#1}
       {
         \bool_lazy_and:nnTF
             { \prop_if_empty_p:c { g__hook_#1_code_prop } }
@@ -4756,18 +5076,24 @@ of this package available from CTAN}
       }
       { \prg_return_true: }
   }
-\prg_new_conditional:Npnn \hook_if_exist:n #1 { p , T , F , TF }
+\prg_new_conditional:Npnn \__hook_if_usable:n #1 { p , T , F , TF }
   {
     \tl_if_exist:cTF { __hook~#1 }
       { \prg_return_true: }
       { \prg_return_false: }
   }
-\prg_new_conditional:Npnn \__hook_if_exist:n #1 { p , T , F , TF }
+\prg_new_conditional:Npnn \__hook_if_structure_exist:n #1 { p , T , F , TF }
   {
     \prop_if_exist:cTF { g__hook_#1_code_prop }
       { \prg_return_true: }
       { \prg_return_false: }
   }
+\prg_new_conditional:Npnn \__hook_if_declared:n #1 { p, T, F, TF }
+  {
+    \tl_if_exist:cTF { g__hook_#1_declared_tl }
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
 \prg_new_conditional:Npnn \__hook_if_reversed:n #1 { p , T , F , TF }
   {
     \if_int_compare:w \cs:w g__hook_#1_reversed_tl \cs_end: 1 < 0 \exp_stop_f:
@@ -4776,47 +5102,54 @@ of this package available from CTAN}
       \prg_return_false:
     \fi:
   }
-\msg_new:nnnn { hooks } { labels-incompatible }
+\__kernel_msg_new:nnnn { hooks } { labels-incompatible }
   {
-    Labels~`#1'~and~`#2'~are~incompatible
-    \str_if_eq:nnF {#3} {??} { ~in~hook~`#3' } .~
+    Labels~'#1'~and~'#2'~are~incompatible
+    \str_if_eq:nnF {#3} {??} { ~in~hook~'#3' } .~
     \int_compare:nNnTF {#4} = { 1 }
       { The~ code~ for~ both~ labels~ will~ be~ dropped. }
       { You~ may~ see~ errors~ later. }
   }
   { LaTeX~found~two~incompatible~labels~in~the~same~hook.~
     This~indicates~an~incompatibility~between~packages.  }
-\msg_new:nnnn { hooks } { exists }
-    { Hook~`#1'~ has~ already~ been~ declared. }
+\__kernel_msg_new:nnnn { hooks } { exists }
+    { Hook~'#1'~ has~ already~ been~ declared. }
     { There~ already~ exists~ a~ hook~ declaration~ with~ this~
       name.\\
       Please~ use~ a~ different~ name~ for~ your~ hook.}
-\msg_new:nnn { hooks } { empty-label }
+\__kernel_msg_new:nnnn { hooks } { hook-disabled }
+  { Cannot~add~code~to~disabled~hook~'#1'. }
+  {
+    The~hook~'#1'~you~tried~to~add~code~to~was~previously~disabled~
+    with~\iow_char:N\\hook_disable:n~or~\iow_char:N\\DisableHook,~so~
+    it~cannot~have~code~added~to~it.
+  }
+\__kernel_msg_new:nnn { hooks } { empty-label }
   {
     Empty~code~label~\msg_line_context:.~
-    Using~`\__hook_currname_or_default:'~instead.
+    Using~'\__hook_currname_or_default:'~instead.
   }
-\msg_new:nnn { hooks } { no-default-label }
+\__kernel_msg_new:nnn { hooks } { no-default-label }
   {
     Missing~(empty)~default~label~\msg_line_context:. \\
     This~command~was~ignored.
   }
-\msg_new:nnnn { hooks } { unknown-rule }
-  { Unknown~ relationship~ `#3'~
-    between~ labels~ `#2'~ and~ `#4'~
-    \str_if_eq:nnF {#1} {??} { ~in~hook~`#1' }. ~
+\__kernel_msg_new:nnnn { hooks } { unknown-rule }
+  { Unknown~ relationship~ '#3'~
+    between~ labels~ '#2'~ and~ '#4'~
+    \str_if_eq:nnF {#1} {??} { ~in~hook~'#1' }. ~
     Perhaps~ a~ missspelling?
   }
   {
     The~ relation~ used~ not~ known~ to~ the~ system.~ Allowed~ values~ are~
-    `before'~ or~ `<',~
-    `after'~ or~ `>',~
-    `incompatible-warning',~
-    `incompatible-error',~
-    `voids'~ or~
-    `unrelated'.
+    'before'~ or~ '<',~
+    'after'~ or~ '>',~
+    'incompatible-warning',~
+    'incompatible-error',~
+    'voids'~ or~
+    'unrelated'.
   }
-\msg_new:nnnn { hooks } { misused-top-level }
+\__kernel_msg_new:nnnn { hooks } { misused-top-level }
   {
     Illegal~\iow_char:N \\AddToHook{#1}[top-level]{...}.\\
     'top-level'~is~reserved~for~the~user's~document.
@@ -4827,36 +5160,67 @@ of this package available from CTAN}
     '\__hook_currname_or_default:'~for~this~\@cls@pkg,~or~another~
     suitable~label.
   }
-\msg_new:nnn { hooks } { set-top-level }
+\__kernel_msg_new:nnn { hooks } { set-top-level }
   {
-    You~cannot~change~the~default~label~#1~`top-level'.~Illegal \\
+    You~cannot~change~the~default~label~#1~'top-level'.~Illegal \\
     \use:nn { ~ } { ~ } \iow_char:N \\#2{#3} \\
     \msg_line_context:.
   }
-\msg_new:nnn { hooks } { ddhl-deprecated }
+\__kernel_msg_new:nnn { hooks } { ddhl-deprecated }
   {
     \iow_char:N \\DeclareDefaultHookLabel~is~deprecated.\\
     Use~\iow_char:N \\SetDefaultHookLabel~instead.\\ \\
     The~deprecated~name~will~be~removed~in~the~next~release.
   }
-\msg_new:nnn { hooks } { extra-pop-label }
+\__kernel_msg_new:nnn { hooks } { extra-pop-label }
   {
     Extra~\iow_char:N \\PopDefaultHookLabel. \\
     This~command~will~be~ignored.
   }
-\msg_new:nnn { hooks } { missing-pop-label }
+\__kernel_msg_new:nnn { hooks } { missing-pop-label }
   {
     Missing~\iow_char:N \\PopDefaultHookLabel. \\
-    The~label~`#1'~was~pushed~but~never~popped.~Something~is~wrong.
+    The~label~'#1'~was~pushed~but~never~popped.~Something~is~wrong.
   }
-\msg_new:nnn { hooks } { should-not-happen }
+\__kernel_msg_new:nnn { hooks } { should-not-happen }
   {
     ERROR!~This~should~not~happen.~#1 \\
     Please~report~at~https://github.com/latex3/latex2e.
   }
+\__kernel_msg_new:nnn { hooks } { provide-disabled }
+  {
+    Can't~ provide~ hook~ '#1'~ because~ it~ is~ disabled!
+  }
+\__kernel_msg_new:nnnn { hooks } { provide-error }
+  {
+    Hook~'#1'~ already~ declared~ as~ a~
+    \__hook_if_reversed:nTF {#1} { reversed } { normal }~ hook!
+  }
+  {
+    You~ attempted~ to~ provide~ the~ hook~'#1'~ as~ a~
+    \__hook_if_reversed:nTF {#1} { normal } { reversed }~ hook,~ but~ it~
+    was~ already~ previously~ declared~ as~ a~
+    \__hook_if_reversed:nTF {#1} { reversed } { normal }~ hook.~
+    A~ redeclaration~ is~ not~ possible.
+  }
 \NewDocumentCommand \NewHook             { m }{ \hook_new:n {#1} }
 \NewDocumentCommand \NewReversedHook     { m }{ \hook_new_reversed:n {#1} }
 \NewDocumentCommand \NewMirroredHookPair { mm }{ \hook_new_pair:nn {#1}{#2} }
+\IncludeInRelease{2021/06/01}%
+         {\hook_provide:n}{Providing~hooks}
+\NewDocumentCommand \ProvideHook         { m }{ \hook_provide:n {#1} }
+\NewDocumentCommand \ProvideReversedHook { m }{ \hook_provide_reversed:n {#1} }
+\NewDocumentCommand \ProvideMirroredHookPair { mm }{ \hook_provide_pair:nn {#1}{#2} }
+\NewDocumentCommand \DisableHook { m }{ \hook_disable:n {#1} }
+\EndIncludeInRelease
+\IncludeInRelease{2020/10/01}
+                 {\hook_provide:n}{Providing~hooks}
+
+\def \ProvideHook#1{}
+\def \ProvideReversedHook#1{}
+\def \ProvideMirroredHookPair#1#2{}
+
+\EndIncludeInRelease
 \NewDocumentCommand \AddToHook { m o +m }
   { \hook_gput_code:nnn {#1} {#2} {#3} }
 \NewDocumentCommand \AddToHookNext { m +m }
@@ -4864,7 +5228,8 @@ of this package available from CTAN}
 \NewDocumentCommand \RemoveFromHook { m o }
   { \hook_gremove_code:nn {#1} {#2} }
 \tl_gset:Nn \g__hook_hook_curr_name_tl { top-level }
-\seq_gput_right:Nn \g__hook_name_stack_seq { top-level }
+\seq_if_empty:NT \g__hook_name_stack_seq
+  { \seq_gput_right:Nn \g__hook_name_stack_seq { top-level } }
 \cs_set_protected:Npn \__hook_tmp:w #1 #2 #3
   {
     \quark_if_recursion_tail_stop:n {#1}
@@ -4875,16 +5240,17 @@ of this package available from CTAN}
   \q_recursion_tail \q_recursion_tail
   \q_recursion_tail \q_recursion_stop
 \tl_gset:Nx \g__hook_hook_curr_name_tl { \@currname }
+\seq_gpop_right:NN \g__hook_name_stack_seq \l__hook_tmpa_tl
 \cs_new_protected:Npn \__hook_curr_name_push:n #1
   { \exp_args:Nx \__hook_curr_name_push_aux:n { \__hook_make_name:n {#1} } }
 \cs_new_protected:Npn \__hook_curr_name_push_aux:n #1
   {
     \tl_if_blank:nTF {#1}
-      { \msg_error:nn { hooks } { no-default-label } }
+      { \__kernel_msg_error:nn { hooks } { no-default-label } }
       {
         \str_if_eq:nnTF {#1} { top-level }
           {
-            \msg_error:nnnnn { hooks } { set-top-level }
+            \__kernel_msg_error:nnnnn { hooks } { set-top-level }
               { to } { PushDefaultHookLabel } {#1}
           }
           {
@@ -4897,7 +5263,7 @@ of this package available from CTAN}
   {
     \seq_gpop:NNTF \g__hook_name_stack_seq \l__hook_return_tl
       { \tl_gset_eq:NN \g__hook_hook_curr_name_tl \l__hook_return_tl }
-      { \msg_error:nn { hooks } { extra-pop-label } }
+      { \__kernel_msg_error:nn { hooks } { extra-pop-label } }
   }
 \tl_gput_right:Nn \@kernel@after@enddocument@afterlastpage
   { \__hook_end_document_label_check: }
@@ -4905,7 +5271,7 @@ of this package available from CTAN}
   {
     \seq_gpop:NNT \g__hook_name_stack_seq \l__hook_return_tl
       {
-        \msg_error:nnx { hooks } { missing-pop-label }
+        \__kernel_msg_error:nnx { hooks } { missing-pop-label }
           { \g__hook_hook_curr_name_tl }
         \tl_gset_eq:NN \g__hook_hook_curr_name_tl \l__hook_return_tl
         \__hook_end_document_label_check:
@@ -4915,7 +5281,7 @@ of this package available from CTAN}
   {
     \seq_if_empty:NTF \g__hook_name_stack_seq
       {
-        \msg_error:nnnnn { hooks } { set-top-level }
+        \__kernel_msg_error:nnnnn { hooks } { set-top-level }
           { for } { SetDefaultHookLabel } {#1}
       }
       { \exp_args:Nx \__hook_set_default_label:n { \__hook_make_name:n {#1} } }
@@ -4924,14 +5290,14 @@ of this package available from CTAN}
   {
     \str_if_eq:nnTF {#1} { top-level }
       {
-        \msg_error:nnnnn { hooks } { set-top-level }
+        \__kernel_msg_error:nnnnn { hooks } { set-top-level }
           { to } { SetDefaultHookLabel } {#1}
       }
       { \tl_gset:Nn \g__hook_hook_curr_name_tl {#1} }
   }
 \NewDocumentCommand \DeclareDefaultHookLabel { m }
   {
-    \msg_error:nn { hooks } { ddhl-deprecated }
+    \__kernel_msg_error:nn { hooks } { ddhl-deprecated }
     \SetDefaultHookLabel {#1}
   }
 \NewDocumentCommand \PushDefaultHookLabel { m }
@@ -4957,21 +5323,21 @@ of this package available from CTAN}
 \@onlypreamble\DeclareDefaultHookRule
 \NewDocumentCommand \ClearHookRule { m m m }
 { \hook_gset_rule:nnnn {#1}{#2}{unrelated}{#3} }
-\cs_new_eq:NN \IfHookExistsTF \hook_if_exist:nTF
 \cs_new_eq:NN \IfHookEmptyTF \hook_if_empty:nTF
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5
+\cs_new_eq:NN \IfHookExistsTF \__hook_if_usable:nTF
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \cs_new_eq:NN \@expl@@@initialize@all@@
               \__hook_initialize_all:
 \cs_new_eq:NN \@expl@@@hook@curr@name@pop@@
               \__hook_curr_name_pop:
-\ExplSyntaxOff
-\EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
-                 {\NewHook}{The hook management}%
+                 {lthooks}{The~hook~management}%
 
-\def\NewHook#1{}
-\def\NewReversedHook#1{}
-\def\NewMirroredHookPair#1#2{}
+\def \NewHook#1{}
+\def \NewReversedHook#1{}
+\def \NewMirroredHookPair#1#2{}
+
+\def \DisableHook #1{}
 
 \long\def\AddToHookNext#1#2{}
 
@@ -4993,12 +5359,475 @@ of this package available from CTAN}
 \long\def \IfHookExistsTF #1#2#3{#3}
 \long\def \IfHookEmptyTF #1#2#3{#2}
 
-\EndIncludeInRelease
+\EndModuleRelease
+\ExplSyntaxOff
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% File: ltcmdhooks.dtx (C) Copyright 2020-2021
+%%       Frank Mittelbach, Phelype Oleinik, LaTeX Team
+%%% From File: ltcmdhooks.dtx
+\def\ltcmdhooksversion{v1.0a}
+\def\ltcmdhooksdate{2021/04/30}
+\ExplSyntaxOn
+\NewModuleRelease{2021/06/01}{ltcmdhooks}
+                 {The~hook~management~system~for~commands}
+\tl_new:N \g_hook_patch_action_list_tl
+\int_new:N \l__hook_patch_num_args_int
+\tl_new:N \l__hook_patch_prefixes_tl
+\tl_new:N \l__hook_patch_param_text_tl
+\tl_new:N \l__hook_patch_replacement_tl
+\prop_new:N \g__hook_delayed_patches_prop
+\cs_new_protected:Npn \__hook_patch_debug:x #1
+  { \__hook_debug:n { \iow_term:x { [lthooks]~#1 } } }
+\cs_generate_variant:Nn \tl_rescan:nn { nV }
+\cs_new_protected:Npn \__hook_try_put_cmd_hook:n #1
+  { \__hook_try_put_cmd_hook:w #1 / / / \s__hook_mark {#1} }
+\cs_new_protected:Npn \__hook_try_put_cmd_hook:w
+    #1 / #2 / #3 / #4 \s__hook_mark #5
+  {
+    \__hook_debug:n { \iow_term:n { ->~Adding~cmd~hook~to~'#2'~(#3): } }
+    \str_case:nnTF {#3}
+        { { before } { } { after } { } }
+      { \exp_args:Nc \__hook_patch_cmd_or_delay:Nnn {#2} {#2} {#3} }
+      { \__kernel_msg_error:nnn { hooks } { wrong-cmd-hook } {#2} {#3} }
+  }
+\cs_new_protected:Npn \__hook_patch_cmd_or_delay:Nnn #1 #2 #3
+  {
+    \__hook_debug:n { \iow_term:n { ->~Add~generic~cmd~hook~for~#2~(#3). } }
+    \__hook_debug:n
+      { \iow_term:n { !~In~the~preamble:~delaying. } }
+    \prop_gput:Nnn \g__hook_delayed_patches_prop { #2 / #3 }
+      { \__hook_cmd_try_patch:nn {#2} {#3} }
+  }
+\cs_new_protected:Npn \__hook_cmd_begindocument_code:
+  {
+    \cs_gset_eq:NN \__hook_patch_cmd_or_delay:Nnn \__hook_patch_command:Nnn
+    \prop_map_function:NN \g__hook_delayed_patches_prop { \use_ii:nn }
+    \prop_gclear:N \g__hook_delayed_patches_prop
+    \cs_undefine:N \__hook_cmd_begindocument_code:
+  }
+\g@addto@macro \@kernel@after@begindocument
+  { \__hook_cmd_begindocument_code: }
+\cs_new_protected:Npn \__hook_cmd_try_patch:nn #1 #2
+  {
+    \__hook_debug:n
+      { \iow_term:x { ->~\string\begin{document}~try~cmd / #1 / #2. } }
+    \__hook_if_declared:nTF { cmd / #1 / #2 }
+      {
+        \__hook_debug:n
+          { \iow_term:n { .->~Giving~up:~hook~already~created. } }
+      }
+      {
+        \cs_if_exist:cT {#1}
+          { \exp_args:Nc \__hook_patch_command:Nnn {#1} {#1} {#2} }
+      }
+  }
+\cs_new_protected:Npn \__hook_patch_command:Nnn #1 #2 #3
+  {
+    \__hook_patch_debug:x { analyzing~'\token_to_str:N #1' }
+    \__hook_patch_debug:x { \token_to_str:N #1 = \token_to_meaning:N #1 }
+    \__hook_patch_check:NNnn \cs_if_exist:NTF #1 { undef }
+      {
+        \__hook_patch_debug:x { ++~control~sequence~is~defined }
+        \__hook_patch_check:NNnn \token_if_macro:NTF #1 { macro }
+          {
+            \__hook_patch_debug:x { ++~control~sequence~is~a~macro }
+            \__hook_patch_check:NNnn \__hook_if_public_command:NTF #1 { expl3 }
+              {
+                \__hook_patch_debug:x { ++~macro~is~not~private }
+                \robust@command@act
+                  \g_hook_patch_action_list_tl #1
+                  \__hook_retokenize_patch:Nnn { #1 {#2} {#3} }
+              }
+          }
+      }
+  }
+\cs_new_protected:Npn \__hook_patch_check:NNnn #1 #2 #3 #4
+  {
+    #1 #2 {#4}
+      {
+        \__kernel_msg_error:nnxx { hooks } { cant-patch }
+          { \token_to_str:N #2 } {#3}
+      }
+  }
+\use:x
+  {
+    \prg_new_protected_conditional:Npnn
+        \exp_not:N \__hook_if_public_command:N ##1 { TF }
+      {
+        \exp_not:N \exp_last_unbraced:Nf
+          \exp_not:N \__hook_if_public_command:w
+            { \exp_not:N \cs_to_str:N ##1 }
+          \tl_to_str:n { _ _ } \s__hook_mark
+      }
+  }
+\exp_last_unbraced:NNNNo
+\cs_new_protected:Npn \__hook_if_public_command:w
+    #1 \tl_to_str:n { _ _ } #2 \s__hook_mark
+  {
+    \tl_if_empty:nTF {#2}
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\tl_gset:Nn \g_hook_patch_action_list_tl
+  {
+    { \@if@DeclareRobustCommand \__hook_patch_DeclareRobustCommand:Nnn }
+    { \@if@newcommand \__hook_patch_newcommand:Nnn }
+    { \__kernel_cmd_if_xparse:NTF \__hook_cmd_patch_xparse:Nnn }
+  }
+\cs_new_protected:Npn \__hook_patch_DeclareRobustCommand:Nnn #1
+  {
+    \exp_args:Nc \@if@newcommand { \cs_to_str:N #1 ~ }
+      { \exp_args:Nc \__hook_patch_newcommand:Nnn }
+      { \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_false_bool }
+        { \cs_to_str:N #1 ~ }
+  }
+\cs_new_protected:Npn \__hook_patch_newcommand:Nnn #1
+  {
+    \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_true_bool
+      { \c_backslash_str \cs_to_str:N #1 }
+  }
+\cs_new_protected:Npn \__hook_cmd_patch_xparse:Nnn #1
+  {
+    \exp_args:NNc \__hook_patch_expand_redefine:NNnn \c_false_bool
+      { \cs_to_str:N #1 ~ code }
+  }
+\cs_new_protected:Npn \__hook_patch_expand_redefine:NNnn #1 #2 #3 #4
+  {
+    \__hook_patch_debug:x { ++~command~can~be~patched~without~rescanning }
+    \int_set:Nn \l__hook_patch_num_args_int
+      {
+        \exp_args:Nf \str_count:n { \cs_argument_spec:N #2 } / 2
+        \bool_if:NT #1 { -1 }
+      }
+    \int_compare:nNnTF { \l__hook_patch_num_args_int } > { \c_zero_int }
+      {
+        \tl_set:Nx \l__hook_patch_param_text_tl
+          { \bool_if:NTF #1 { [####1] } {  ####1  } }
+        \tl_set:Nx \l__hook_patch_replacement_tl
+          { \bool_if:NTF #1 { [####1] } { {####1} } }
+        \int_step_inline:nnn { 2 } { \l__hook_patch_num_args_int }
+          {
+            \tl_put_right:Nn \l__hook_patch_param_text_tl    { ## ####1 }
+            \tl_put_right:Nn \l__hook_patch_replacement_tl { { ## ####1 } }
+          }
+      }
+      {
+        \tl_clear:N \l__hook_patch_param_text_tl
+        \tl_clear:N \l__hook_patch_replacement_tl
+      }
+    \group_begin:
+      \int_set:Nn \tex_escapechar:D { `\/ }
+      \use:x
+        {
+    \group_end:
+    \tl_set:Nx \exp_not:N \l__hook_patch_prefixes_tl
+      { \exp_not:N \__hook_make_prefixes:w \cs_prefix_spec:N #2 / / }
+        }
+    \use:x
+      {
+        \l__hook_patch_prefixes_tl \tex_def:D
+            \exp_not:N #2 \exp_not:V \l__hook_patch_param_text_tl
+          {
+            \str_if_eq:nnT {#4} { before }
+              { \exp_not:N \UseHook { cmd / #3 / #4 } }
+            \exp_args:No \exp_not:o
+              { \exp_after:wN #2 \l__hook_patch_replacement_tl }
+            \str_if_eq:nnT {#4} { after }
+              { \exp_not:N \UseHook { cmd / #3 / #4 } }
+          }
+      }
+  }
+\cs_new:Npn \__hook_make_prefixes:w / #1 /
+  {
+    \tl_if_empty:nF {#1}
+      {
+        \exp_not:c { tex_ \tl_trim_spaces:n {#1} :D }
+        \__hook_make_prefixes:w /
+      }
+  }
+\cs_new_protected:Npn \__hook_retokenize_patch:Nnn #1 #2 #3
+  {
+    \__hook_patch_debug:x { ..~command~can~only~be~patched~by~rescanning }
+    \str_if_eq:eeTF { \cs_argument_spec:N #1 } { }
+      { \__hook_patch_expand_redefine:NNnn \c_false_bool #1 {#2} {#3} }
+      {
+        \tl_set:Nx \l__hook_tmpa_tl
+          {
+            \int_compare:nNnTF { \char_value_catcode:n {`\@ } } = { 12 }
+              { \exp_not:N \makeatletter } { \exp_not:N \makeatother }
+          }
+        \tl_set:Nx \l__hook_tmpb_tl
+          {
+            \bool_if:NTF \l__kernel_expl_bool
+              { \ExplSyntaxOff } { \ExplSyntaxOn }
+          }
+        \use:x
+          {
+            \exp_not:N \__hook_try_patch_with_catcodes:Nnnnw
+                \exp_not:n { #1 {#2} {#3} }
+              { \prg_do_nothing: }
+              { \exp_not:V \l__hook_tmpa_tl } % @
+              { \exp_not:V \l__hook_tmpb_tl } % _:
+              {
+                \exp_not:V \l__hook_tmpa_tl   % @
+                \exp_not:V \l__hook_tmpb_tl   % _:
+              }
+          }
+              \q_recursion_tail \q_recursion_stop
+          {
+            \__kernel_msg_error:nnxx { hooks } { cant-patch }
+              { \c_backslash_str #2 } { retok }
+          }
+      }
+  }
+\cs_new_protected:Npn \__hook_try_patch_with_catcodes:Nnnnw #1 #2 #3 #4
+  {
+    \quark_if_recursion_tail_stop_do:nn {#4} { \use:n }
+    \__hook_patch_debug:x { ++~trying~to~patch~by~retokenization }
+    \__hook_cmd_if_scanable:NnTF {#1} {#4}
+      {
+        \__hook_patch_debug:x { ++~macro~can~be~retokenized~cleanly }
+        \__hook_patch_debug:x { ==~retokenizing~macro~now }
+        \__hook_patch_retokenize:Nnnn #1 {#2} {#3} {#4}
+        \use_i_delimit_by_q_recursion_stop:nw \use_none:n
+      }
+      {
+        \__hook_patch_debug:x { --~macro~cannot~be~retokenized~cleanly }
+        \__hook_try_patch_with_catcodes:Nnnnw #1 {#2} {#3}
+      }
+  }
+\cs_new_eq:NN \kerneltmpDoNotUse !
+\cs_new_protected:Npn \__hook_patch_required_catcodes:
+  {
+    \char_set_catcode_escape:N \\
+    \char_set_catcode_group_begin:N \{
+    \char_set_catcode_group_end:N \}
+    \char_set_catcode_parameter:N \#
+    % \int_set:Nn \tex_endlinechar:D { -1 }
+    % \int_set:Nn \tex_newlinechar:D { -1 }
+  }
+\prg_new_protected_conditional:Npnn \__hook_cmd_if_scanable:Nn #1 #2 { TF }
+  {
+    \cs_set_eq:NN \kerneltmpDoNotUse \scan_stop:
+    \cs_set_eq:NN \__hook_tmp:w \scan_stop:
+    \use:x
+      {
+        \cs_set:Npn \__hook_tmp:w
+            ####1 \tl_to_str:n { macro: } ####2 -> ####3 \s__hook_mark
+          { ####1 \def \kerneltmpDoNotUse ####2   {####3} }
+        \tl_set:Nx \exp_not:N \l__hook_tmpa_tl
+          { \exp_not:N \__hook_tmp:w \token_to_meaning:N #1 \s__hook_mark }
+      }
+    \tl_rescan:nV { #2 \__hook_patch_required_catcodes: } \l__hook_tmpa_tl
+    \token_if_eq_meaning:NNTF #1 \kerneltmpDoNotUse
+      { \prg_return_true: }
+      { \prg_return_false: }
+  }
+\cs_new_protected:Npn \__hook_patch_retokenize:Nnnn #1 #2 #3 #4
+  {
+    \cs_set_eq:NN \kerneltmpDoNotUse \scan_stop:
+    \cs_set_eq:NN \__hook_tmp:w \scan_stop:
+    \use:x
+      {
+        \cs_set:Npn \__hook_tmp:w
+            ####1 \tl_to_str:n { macro: } ####2 -> ####3 \s__hook_mark
+          {
+            ####1 \def \kerneltmpDoNotUse ####2
+              {
+                \str_if_eq:nnT {#3} { before }
+                  { \token_to_str:N \UseHook { cmd / #2 / #3 } }
+                ####3
+                \str_if_eq:nnT {#3} { after }
+                  { \token_to_str:N \UseHook { cmd / #2 / #3 } }
+              }
+          }
+        \tl_set:Nx \exp_not:N \l__hook_tmpa_tl
+          { \exp_not:N \__hook_tmp:w \token_to_meaning:N #1 \s__hook_mark }
+      }
+    \tl_rescan:nV { #4 \__hook_patch_required_catcodes: } \l__hook_tmpa_tl
+    \cs_set_eq:NN #1 \kerneltmpDoNotUse
+  }
+\__kernel_msg_new:nnnn { hooks } { wrong-cmd-hook }
+  {
+    Command~hook~`cmd/#1/#2'~invalid.\\
+    The~hook~should~be~`cmd/#1/before'~or~`cmd/#1/after'.
+  }
+  {
+    You~tried~to~add~a~hook~to~command~\iow_char:N \\#1,~but~`#2'~
+    is~an~invalid~position.~Only~`before'~or~`after'~are~allowed.
+  }
+\__kernel_msg_new:nnnn { hooks } { cant-patch }
+  {
+    Command~`#1'~cannot~have~hooks~because~it~
+    \__hook_unpatchable_cases:n {#2} .
+  }
+  {
+    You~tried~to~add~a~hook~to~`#1',~but~LaTeX~was~not~able~to~
+    add~the~hook~to~that~command~because~`#1'~
+    \__hook_unpatchable_cases:n {#2} .
+  }
+\cs_new:Npn \__hook_unpatchable_cases:n #1
+  {
+    \str_case:nn {#1}
+      {
+        { undef } { doesn't~exist }
+        { macro } { is~not~a~macro }
+        { expl3 } { is~a~private~expl3~macro }
+        { retok } { can't~be~retokenized~cleanly }
+      }
+  }
+\IncludeInRelease{0000/00/00}{ltcmdhooks}%
+                 {The~hook~management~system~for~commands}
+
+\cs_set_eq:NN \__hook_cmd_begindocument_code: \prg_do_nothing:
+
+\EndModuleRelease
+\ExplSyntaxOff
 %%% From File: ltalloc.dtx
 %%% From File: ltcntrl.dtx
 %%% From File: lterror.dtx
 %%% From File: ltpar.dtx
+%% File: ltpara.dtx (C) Copyright 2020-2021
+%%% From File: ltpara.dtx
+\def\ltparaversion{v1.0f}
+\def\ltparadate{2021/04/16}
+
+
+\ExplSyntaxOn
+\NewModuleRelease{2021/06/01}{ltpara}
+                 {Paragraph~handling~and~hooks}
+\hook_new_pair:nn{para/before}{para/after}
+\hook_new_pair:nn{para/begin}{para/end}
+\let \@kernel@before@para@before \@empty
+\let \@kernel@before@para@begin  \@empty
+\let \@kernel@after@para@end     \@empty
+\let \@kernel@after@para@after   \@empty
+\tl_new:N \g__para_standard_everypar_tl
+\tl_gset:Nn \g__para_standard_everypar_tl {
+  \box_gset_to_last:N \g_para_indent_box
+  \group_begin:
+    \tex_par:D
+  \group_end:
+  \tex_everypar:D { \__kernel_msg_error:nnnn {para}{mode}{before}{vertical} }
+  \@kernel@before@para@before
+  \hook_use:n {para/before}
+  \group_begin:
+    \tex_everypar:D {}
+    \skip_zero:N \tex_parskip:D
+    \tex_noindent:D
+  \group_end:
+  \tex_everypar:D{\g__para_standard_everypar_tl}
+  \@kernel@before@para@begin
+  \hook_use:n {para/begin}
+  \if_mode_horizontal: \else:
+    \__kernel_msg_error:nnnn {para}{mode}{begin}{vertical} \fi:
+  \__para_handle_indent:
+}
+\tex_everypar:D{\g__para_standard_everypar_tl}
+\newtoks \everypar
+
+\tl_gput_right:Nx \g__para_standard_everypar_tl {
+    \exp_not:N \the
+    \exp_not:N \toks
+    \the \allocationnumber
+    \c_space_tl
+}
+\box_new:N \g_para_indent_box
+
+\cs_new:Npn \__para_handle_indent: {
+  \box_use_drop:N \g_para_indent_box
+}
+\cs_new:Npn \para_omit_indent: {
+  \box_gclear:N \g_para_indent_box
+}
+\cs_set_eq:NN \IndentBox \g_para_indent_box
+\cs_set_eq:NN \OmitIndent \para_omit_indent:
+\cs_new_protected:Npn \para_end: {
+  \mode_if_horizontal:TF {
+    \mode_if_inner:F {
+         \tex_unskip:D
+         \hook_use:n{para/end}
+         \@kernel@after@para@end
+         \mode_if_horizontal:TF {
+           \if_int_compare:w 0 < \tex_lastnodetype:D
+             \tex_kern:D \c_zero_dim
+           \fi:
+           \tex_par:D
+           \hook_use:n{para/after}
+           \@kernel@after@para@after
+         }
+         { \__kernel_msg_error:nnnn {para}{mode}{end}{horizontal} }
+    }
+  }
+  \tex_par:D
+}
+\cs_new:Npn \para_raw_indent: {
+  \mode_if_vertical:TF
+       {
+         \tex_everypar:D {
+           \box_gset_to_last:N \g_para_indent_box
+           \tex_everypar:D { \g__para_standard_everypar_tl }
+           \__para_handle_indent:
+           \the\everypar }
+       }
+       { \__kernel_msg_error:nn {para}{raw} }
+  \tex_indent:D
+}
+\cs_new:Npn \para_raw_noindent: {
+  \mode_if_vertical:TF
+       {
+         \tex_everypar:D {
+           \tex_everypar:D { \g__para_standard_everypar_tl }
+           \the\everypar }
+       }
+       { \__kernel_msg_error:nn {para}{raw} }
+  \tex_noindent:D
+}
+\cs_new_eq:NN \para_raw_end: \tex_par:D
+\cs_set_eq:NN \RawIndent   \para_raw_indent:
+\cs_set_eq:NN \RawNoindent \para_raw_noindent:
+\cs_set_eq:NN \RawParEnd   \para_raw_end:
+\cs_set_eq:NN \par     \para_end:
+\cs_set_eq:NN \@@par   \para_end:
+\cs_set_eq:NN \endgraf \para_end:
+\everypar{\@nodocument} %% To get an error if text appears before the
+\__kernel_msg_new:nnnn {para} {mode}
+  {
+    Illegal~mode~ change~ in~ hook~ 'para/#1'.\\
+    Hook~ code~ did~ not~ remain~ in~ #2~ mode.
+  }
+  {
+    Paragraph~ hooks~ cannot~ change~ the~ TeX~ mode~ without~ causing~
+    endless~ recursion.~ The~ hook~ code~ in~ 'para/#1'~ needs~ to~ stay~
+    in~ #2~ mode,~ but~ it~ didn't.~ Examine~ the~ hook~
+    code~ with~ \ShowHook~ to~ find~ the~ issue.
+  }
+\__kernel_msg_new:nnnn {para} {raw}
+  {
+     Paragraph started while not in vertical mode.
+  }
+  {
+    Starting a paragraph with \RawIndent or \RawNoindent
+    (or \para_raw_indent: or \para_raw_noindent:) is only
+    allowed if LaTeX is in vertical mode.
+  }
+
+\IncludeInRelease{0000/00/00}%
+                 {ltpara}{Undo~hooks~for~paragraphs}
+
+\let \OmitIndent  \@undefined
+\let \IndentBox   \@undefined
+\let \RawIndent   \@undefined
+\let \RawNoindent \@undefined
+\let \RawParEnd   \@undefined
+
+\cs_set_eq:NN \par     \tex_par:D
+\cs_set_eq:NN \@@par   \tex_par:D
+\cs_set_eq:NN \endgraf \tex_par:D
+
+\EndModuleRelease
+\ExplSyntaxOff
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%% From File: ltspace.dtx
 \IncludeInRelease{2019/10/01}%
                  {\pagebreak}{Make commands robust}%
@@ -5402,8 +6231,6 @@ of this package available from CTAN}
   \let\expandafter\noexpand\csname
        __hook env/document/begin\endcsname
   \noexpand\@empty}
-\let \@kernel@before@begindocument \@empty
-\let \@kernel@after@begindocument \@empty
 
 \EndIncludeInRelease
 \IncludeInRelease{2017/04/15}%
@@ -5668,6 +6495,52 @@ of this package available from CTAN}
 \DeclareRobustCommand\IfFileExists[1]{%
   \set@curr@file{#1}%
   \expandafter\IfFileExists@\expandafter{\@curr@file}}
+\EndIncludeInRelease
+\IncludeInRelease{0000/00/00}%
+                 {\quote@name}{Quote file names}%
+
+\let\quote@name\@undefined
+\let\quote@@name\@undefined
+\let\unquote@name\@undefined
+
+\long\def \IfFileExists#1#2#3{%
+  \openin\@inputcheck#1 %
+  \ifeof\@inputcheck
+    \ifx\input@path\@undefined
+      \def\reserved@a{#3}%
+    \else
+      \def\reserved@a{\@iffileonpath{#1}{#2}{#3}}%
+    \fi
+  \else
+    \closein\@inputcheck
+    \edef\@filef@und{#1 }%
+    \def\reserved@a{#2}%
+  \fi
+  \reserved@a}
+
+\EndIncludeInRelease
+\IncludeInRelease{2021/06/01}%
+                 {\IfFileExists@}{manage unbalanced conditionals}
+\long\def \IfFileExists@#1#2#3{%
+  \openin\@inputcheck"#1" %
+  \ifeof\@inputcheck
+    \ifx\input@path\@undefined
+      \let\reserved@a\@secondoftwo
+    \else
+      \def\reserved@a{\@iffileonpath{#1}}%
+    \fi
+  \else
+    \closein\@inputcheck
+    \edef\@filef@und{"#1" }%
+    \let\reserved@a\@firstoftwo
+  \fi
+  \expandafter\def\expandafter\reserved@a
+    \expandafter{\reserved@a{#2}{#3}}%
+\reserved@a}
+\EndIncludeInRelease
+\IncludeInRelease{2019/10/01}%
+                 {\IfFileExists@}{manage unbalanced conditionals}
+
 \long\def \IfFileExists@#1#2#3{%
   \openin\@inputcheck"#1" %
   \ifeof\@inputcheck
@@ -5682,6 +6555,16 @@ of this package available from CTAN}
     \def\reserved@a{#2}%
   \fi
   \reserved@a}
+\EndIncludeInRelease
+\IncludeInRelease{0000/00/00}%
+                 {\IfFileExists@}{manage unbalanced conditionals}
+
+\let\IfFileExists@\@undefined
+
+
+\EndIncludeInRelease
+\IncludeInRelease{2019/10/01}%
+                 {\@iffileonpath}{Quote file names}
 \long\def\@iffileonpath#1{%
   \let\reserved@a\@secondoftwo
   \expandafter\@tfor\expandafter\reserved@b\expandafter
@@ -5696,28 +6579,7 @@ of this package available from CTAN}
   \reserved@a}
 \EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
-                 {\quote@name}{Quote file names}%
-
-\let\quote@name\@undefined
-\let\quote@@name\@undefined
-\let\unquote@name\@undefined
-
-\let\IfFileExists@\@undefined
-
-\long\def \IfFileExists#1#2#3{%
-  \openin\@inputcheck#1 %
-  \ifeof\@inputcheck
-    \ifx\input@path\@undefined
-      \def\reserved@a{#3}%
-    \else
-      \def\reserved@a{\@iffileonpath{#1}{#2}{#3}}%
-    \fi
-  \else
-    \closein\@inputcheck
-    \edef\@filef@und{#1 }%
-    \def\reserved@a{#2}%
-  \fi
-  \reserved@a}
+                 {\quote@name}{Quote file names}
 
 \long\def\@iffileonpath#1{%
   \let\reserved@a\@secondoftwo
@@ -6157,13 +7019,25 @@ of this package available from CTAN}
                              }%
     \fi}%
 \EndIncludeInRelease
+\IncludeInRelease{2021/06/01}%
+                 {\usefont}{Force font face}%
+\DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
+   \edef\f@family{#2}%
+   \set@target@series{#3}%
+   \edef\f@shape{#4}%
+   \let\delayed@f@adjustment\@empty
+   \selectfont
+   \ignorespaces}
+\EndIncludeInRelease
 \IncludeInRelease{2020/02/02}%
                  {\usefont}{Drop m in usefont}%
+
 \DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
    \edef\f@family{#2}%
    \set@target@series{#3}%
    \edef\f@shape{#4}\selectfont
    \ignorespaces}
+
 \EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
                  {\usefont}{Drop m in usefont}%
@@ -6785,7 +7659,7 @@ of this package available from CTAN}
 \let\DeclareFontSeriesChangeRule\@undefined
 
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\fontseries}{delay fontseries update}%
 \DeclareRobustCommand\fontseries[1]{\@forced@seriesfalse
     \expandafter\def\expandafter\delayed@f@adjustment\expandafter
@@ -6805,9 +7679,7 @@ of this package available from CTAN}
                                          \edef\f@series{#1}}
 \let\delayed@f@adjustment\@undefined
 
-\ifx\@forced@seriestrue\@undefined \else
-  \expandafter\newif\csname if@forced@series\endcsname
-\fi
+\expandafter\newif\csname if@forced@series\endcsname
 
 \EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
@@ -6982,7 +7854,7 @@ of this package available from CTAN}
 \let\sscdefault\@undefined
 
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
    {\fontshape}{Font shape change}%
 \DeclareRobustCommand\fontshape[1]
    {\expandafter\def\expandafter\delayed@f@adjustment\expandafter
@@ -7113,7 +7985,7 @@ of this package available from CTAN}
 %% Copyright (C) 1989-97 by Frank Mittelbach and Rainer Sch\"opf.
 %% Copyright (C) 1994-97 by LaTeX Project. All rights reserved.
 
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\selectfont}{Add hook to \selectfont}%
 \DeclareRobustCommand\selectfont
         {%
@@ -7137,6 +8009,7 @@ of this package available from CTAN}
       \fi
       \let\delayed@f@adjustment\@empty
     \fi
+    \@forced@seriesfalse
     \xdef\font@name{%
       \csname\curr@fontshape/\f@size\endcsname}%
     \pickup@font
@@ -7714,6 +8587,9 @@ of this package available from CTAN}
    \prepare@family@series@update{tt}\ttdefault
    \@ttfamilyhook
    \selectfont}
+\let\@rmfamilyhook\@empty
+\let\@sffamilyhook\@empty
+\let\@ttfamilyhook\@empty
 
 
 \EndIncludeInRelease
@@ -7852,18 +8728,53 @@ of this package available from CTAN}
 \DeclareRobustCommand\symbol[1]{\char#1\relax}
 
 \EndIncludeInRelease
-\IncludeInRelease{2020/02/02}%
+\IncludeInRelease{2021/06/01}%
                  {\normalfont}{Add hook to \normalfont}%
 \DeclareRobustCommand\normalfont{%
    \fontencoding\encodingdefault
    \edef\f@family{\familydefault}%
    \edef\f@series{\seriesdefault}%
    \edef\f@shape{\shapedefault}%
+   \let\delayed@f@adjustment\@empty
    \UseHook{normalfont}%
    \@defaultfamilyhook        % hookname from 2020/02 will vanish
    \selectfont}
 \let\reset@font\normalfont
 \EndIncludeInRelease
+
+\IncludeInRelease{2020/10/01}%
+                 {\normalfont}{Add hook to \normalfont}%
+
+\DeclareRobustCommand\normalfont{%
+   \fontencoding\encodingdefault
+   \edef\f@family{\familydefault}%
+   \edef\f@series{\seriesdefault}%
+   \edef\f@shape{\shapedefault}%
+   \UseHook{normalfont}%
+   \@defaultfamilyhook        % hookname from 2020/02 will vanish
+   \selectfont}
+
+\let\reset@font\normalfont
+
+\EndIncludeInRelease
+
+\IncludeInRelease{2020/02/02}%
+                 {\normalfont}{Add hook to \normalfont}%
+
+\DeclareRobustCommand\normalfont{%
+   \fontencoding\encodingdefault
+   \edef\f@family{\familydefault}%
+   \edef\f@series{\seriesdefault}%
+   \edef\f@shape{\shapedefault}%
+   \@defaultfamilyhook
+   \selectfont}
+
+\let\reset@font\normalfont
+
+\let\@defaultfamilyhook\@empty
+
+\EndIncludeInRelease
+
 \IncludeInRelease{0000/00/00}%
                  {\normalfont}{Add hook to \normalfont}%
 
@@ -7958,8 +8869,8 @@ of this package available from CTAN}
 \let\textssc\@undefined
 \EndIncludeInRelease
 %%% From File: lttextcomp.dtx
-\IncludeInRelease{2020/02/02}%
-                 {\oldstylenums}{Old style numerals}%
+\NewModuleRelease{2020/02/02}{lttextcomp}
+                 {Text Companion symbols}
 \DeclareRobustCommand\legacyoldstylenums[1]{%
    \begingroup
     \spaceskip\fontdimen\tw@\font
@@ -7996,24 +8907,6 @@ of this package available from CTAN}
   \egroup
 }
 \def\textcompsubstdefault{\rmsubstdefault}
-\EndIncludeInRelease
-\IncludeInRelease{0000/00/00}%
-                 {\oldstylenums}{Old style numerals}%
-
-\DeclareRobustCommand\oldstylenums[1]{%
-   \begingroup
-    \spaceskip\fontdimen\tw@\font
-    \usefont{OML}{\rmdefault}{\f@series}{it}%
-    \mathgroup\symletters #1%
-   \endgroup
-}
-\let\legacyoldstylenums\@undefined
-\def\textcompsubstdefault{cmr}
-
-\EndIncludeInRelease
-
-\IncludeInRelease{2020/02/02}%
-   {\DeclareEncodingSubset}{Text companion symbols}%
 \def\DeclareEncodingSubset#1#2{%
   \DeclareEncodingSubset@aux{#1}#2*\DeclareEncodingSubset@aux
 }
@@ -8576,9 +9469,19 @@ of this package available from CTAN}
 \DeclareTextSymbolDefault{\textlegacyperiodcentered}{OMS}
 \DeclareTextSymbolDefault{\textlegacysection}{OMS}
 
-\EndIncludeInRelease
+
 \IncludeInRelease{0000/00/00}%
-   {\DeclareEncodingSubset}{Text companion symbols}%
+     {lttextcomp}{Undefine text companion symbols}%
+
+\DeclareRobustCommand\oldstylenums[1]{%
+   \begingroup
+    \spaceskip\fontdimen\tw@\font
+    \usefont{OML}{\rmdefault}{\f@series}{it}%
+    \mathgroup\symletters #1%
+   \endgroup
+}
+\let\legacyoldstylenums\@undefined
+\def\textcompsubstdefault{cmr}
 
 \let\DeclareEncodingSubset\@undefined
 \let\CheckEncodingSubset\@undefined
@@ -8769,7 +9672,7 @@ of this package available from CTAN}
 \let\textlegacyperiodcentered\@undefined
 \let\textlegacysection\@undefined
 
-\EndIncludeInRelease
+\EndModuleRelease
 
 
 %%% From File: ltpageno.dtx
@@ -8902,7 +9805,7 @@ of this package available from CTAN}
 \let\@enddocument@kernel@warnings\@undefined
 
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@kernel@before@enddocument}{kernel before hook}%
 \def\@kernel@before@enddocument{\par}
 \EndIncludeInRelease
@@ -9498,7 +10401,7 @@ of this package available from CTAN}
     \mb@b
     \kern\z@}}
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\color@begingroup}{color group settings}%
 \let\color@begingroup\begingroup
 \def\color@endgroup{\endgraf\endgroup}
@@ -9599,7 +10502,7 @@ of this package available from CTAN}
   \baselineskip\normalbaselineskip
   \sloppy}
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@mpfootnotetext}{footnotetext tagging}%
 \long\def\@mpfootnotetext#1{%
   \global\setbox\@mpfootins\vbox{%
@@ -10574,7 +11477,7 @@ of this package available from CTAN}
   \@fpbot \@dblfpbot
 }%
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@savemarbox}{Explicit par for marginpar}%
 \long\def \@savemarbox #1#2{%
   \global\setbox #1%
@@ -10642,7 +11545,7 @@ of this package available from CTAN}
                  {\@textsubscript}{subscript baseline}%
 \let\@textsubscript\@undefined
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@footnotetext}{footnotetext tagging}%
 \long\def\@footnotetext#1{\insert\footins{%
     \reset@font\footnotesize
@@ -10677,7 +11580,7 @@ of this package available from CTAN}
     \color@endgroup}}%
 
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\footref}{Add footref}%
 \def\footref#1{%
   \begingroup
@@ -10686,15 +11589,15 @@ of this package available from CTAN}
   \@footnotemark
 }
 \EndIncludeInRelease
-%%<latexrelease>\IncludeInRelease{0000/00/00}%
-%%<latexrelease>                 {\footref}{Add footref}%
-%%<latexrelease>
-%%<latexrelease>\let\footref\@undefined
-%%<latexrelease>
-%%<latexrelease>\EndIncludeInRelease
+\IncludeInRelease{0000/00/00}%
+                 {\footref}{Add footref}%
+
+  % \let\footref\@undefined
+
+\EndIncludeInRelease
 %%% From File: ltidxglo.dtx
 %%% From File: ltbibl.dtx
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\nocite}{Allow nocite in preamble}%
 \def\nocite#1{\@bsphack
   \ifx\@onlypreamble\document
@@ -10791,12 +11694,25 @@ of this package available from CTAN}
 
 \IncludeInRelease{0000/00/00}{\@pushfilename}%
   {Add \@expl@push@filename@@ and \@expl@push@filename@aux@@}%
+\ifnum\sourceLaTeXdate<20200202\relax
+  \GenericInfo{}{Defining 00-00-00\string\@pushfilename.}
 \def\@pushfilename{%
   \xdef\@currnamestack{%
     {\@currname}%
     {\@currext}%
     {\the\catcode`\@}%
     \@currnamestack}}
+\else
+  \GenericInfo{}{Defining 2020-02-02\string\@pushfilename.}
+\def\@pushfilename{%
+  \@expl@push@filename@@
+  \xdef\@currnamestack{%
+    {\@currname}%
+    {\@currext}%
+    {\the\catcode`\@}%
+    \@currnamestack}%
+    \@expl@push@filename@aux@@}
+\fi
 \EndIncludeInRelease
 \@onlypreamble\@pushfilename
 
@@ -10816,7 +11732,14 @@ of this package available from CTAN}
 
 \IncludeInRelease{0000/00/00}{\@popfilename}%
   {Add \@expl@push@filename@@ and \@expl@push@filename@aux@@}%
+\ifnum\sourceLaTeXdate<20200202\relax
+  \GenericInfo{}{Defining 00-00-00\string\@popfilename.}
 \def\@popfilename{\expandafter\@p@pfilename\@currnamestack\@nil}
+\else
+  \GenericInfo{}{Defining 2020-02-02\string\@popfilename.}
+\def\@popfilename{\expandafter\@p@pfilename\@currnamestack\@nil
+  \@expl@pop@filename@@}
+\fi
 \EndIncludeInRelease
 \@onlypreamble\@popfilename
 
@@ -10978,7 +11901,7 @@ of this package available from CTAN}
 \let\ProvidesClass\ProvidesPackage
 \@onlypreamble\ProvidesClass
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@pass@ptions}{Raw option lists}%
 \def\@pass@ptions#1#2#3{%
   \@expl@@@filehook@set@curr@file@@nNN
@@ -11022,7 +11945,7 @@ of this package available from CTAN}
       {\csname opt@#3.#1\endcsname,}%
     \zap@space#2 \@empty}}
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\OptionNotUsed}{filter unused option list}%
 \def\@remove@eq@value#1=#2\@nil{#1}
 \def\OptionNotUsed{%
@@ -11042,6 +11965,38 @@ of this package available from CTAN}
       \CurrentOption}%
   \fi}
 \EndIncludeInRelease
+\IncludeInRelease{2021/06/01}%
+                 {\@xprocess@ptions}{safer @xprocess@ptions}%
+\def\@xprocess@ptions{%
+  \ifx\@currext\@clsextension\else
+   \ifx\@classoptionslist\relax\else
+    \@for\CurrentOption:=\@classoptionslist\do{%
+      \ifx\CurrentOption\@empty\else
+        \@ifundefined{ds@\CurrentOption}{}{%
+          \@use@ption
+          \expandafter\let\csname ds@\CurrentOption\endcsname\@empty
+        }%
+      \fi}%
+    \fi
+  \fi
+  \@process@pti@ns}
+\EndIncludeInRelease
+\IncludeInRelease{0000/00/00}%
+                 {\@xprocess@ptions}{safer @xprocess@ptions}%
+\let\@remove@eq@value\@undefined
+\def\@xprocess@ptions{%
+  \ifx\@currext\@clsextension\else
+    \@for\CurrentOption:=\@classoptionslist\do{%
+      \ifx\CurrentOption\@empty\else
+        \@expandtwoargs\in@{,\CurrentOption,}{,\@declaredoptions,}%
+        \ifin@
+          \@use@ption
+          \expandafter\let\csname ds@\CurrentOption\endcsname\@empty
+        \fi
+      \fi}%
+  \fi
+  \@process@pti@ns}
+\EndIncludeInRelease
 \IncludeInRelease{2020/10/01}%
                  {\@process@pti@ns}{Unused options issue}%
 \def\@process@pti@ns{%
@@ -11074,7 +12029,7 @@ of this package available from CTAN}
   \let\@fileswith@pti@ns\@@fileswith@pti@ns
   \AtEndOfPackage{\let\@unprocessedoptions\relax}}
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\@use@ption}{filter unused option list}%
 \def\@use@ption{%
   \@expandtwoargs\@removeelement
@@ -11455,14 +12410,12 @@ of this package available from CTAN}
       \let\write\@gobbletwo%
       \let\closeout\@gobble%
     \else%
-      \edef\reserved@a{#1}%
-      \edef\reserved@a{\detokenize\expandafter{\reserved@a}}%
       \edef\reserved@b{\detokenize\expandafter{\jobname}}%
-      \ifx\reserved@a\reserved@b%
+      \ifx\@curr@file\reserved@b%
         \@fileswtrue%
       \else%
         \edef\reserved@b{\reserved@b\detokenize{.tex}}%
-        \ifx\reserved@a\reserved@b
+        \ifx\@curr@file\reserved@b
           \@fileswtrue%
         \fi%
       \fi%
@@ -11752,8 +12705,8 @@ of this package available from CTAN}
 \endgroup%
 \EndIncludeInRelease
 %%% From File: ltfilehook.dtx
-\providecommand\ltfilehookversion{v1.0g}
-\providecommand\ltfilehookdate{2021/02/08}
+\providecommand\ltfilehookversion{v1.0j}
+\providecommand\ltfilehookdate{2021/04/29}
 \IncludeInRelease{2020/10/01}%
                  {\CurrentFile}{Hook management file}%
 \ExplSyntaxOn
@@ -11805,7 +12758,8 @@ of this package available from CTAN}
 \cs_new:Npn \__filehook_drop_extension_aux:nnn #1 #2 #3
    { \tl_if_empty:nF {#1} { #1 / } #2 }
 \tl_new:N \l__filehook_internal_tl
-\seq_new:N \g__filehook_input_file_seq
+\seq_if_exist:NF \g__filehook_input_file_seq
+  { \seq_new:N \g__filehook_input_file_seq }
 \cs_new_protected:Npn \__filehook_file_push:
   {
     \seq_gpush:Nx \g__filehook_input_file_seq
@@ -11819,7 +12773,7 @@ of this package available from CTAN}
     \seq_gpop:NNTF \g__filehook_input_file_seq \l__filehook_internal_tl
       { \exp_after:wN \__filehook_file_pop_assign:nnnn \l__filehook_internal_tl }
       {
-        \msg_error:nnn { hooks } { should-not-happen }
+        \__kernel_msg_error:nnn { hooks } { should-not-happen }
           { Tried~to~pop~from~an~empty~file~name~stack. }
       }
   }
@@ -11991,12 +12945,13 @@ of this package available from CTAN}
 \let \undeclare@file@substitution \@gobble
 
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
           {\set@curr@file}{Setting current file name}%
 \def\set@curr@file#1{%
   \begingroup
     \escapechar\m@ne
     \let\protect\string
+    \edef~{\string~}%
     \expandafter\def\csname\expandafter\endcsname
       \expandafter{\csname\endcsname}%
     \@expl@@@filehook@if@no@extension@@nTF{#1}%
@@ -12013,6 +12968,7 @@ of this package available from CTAN}
   \endgroup}
 \EndIncludeInRelease
 \IncludeInRelease{2020/10/01}%
+          {\set@curr@file}{Setting current file name}%
 \def\set@curr@file#1{%
   \begingroup
     \escapechar\m@ne
@@ -12180,7 +13136,7 @@ of this package available from CTAN}
 \cs_new_eq:NN \@expl@@@filehook@drop@extension@@N
               \__filehook_drop_extension:N
 \cs_new_eq:NN \@expl@@@filehook@file@push@@
-               \__filehook_file_push:
+              \__filehook_file_push:
 \cs_new_eq:NN \@expl@@@filehook@file@pop@@
               \__filehook_file_pop:
 \cs_new_eq:NN \@expl@@@filehook@file@pop@assign@@nnnn
@@ -12199,7 +13155,7 @@ of this package available from CTAN}
 %%
 %%% From File: ltshipout.dtx
 \providecommand\ltshipoutversion{v1.0i}
-\providecommand\ltshipoutdate{2021/01/25}
+\providecommand\ltshipoutdate{2021/03/17}
 \IncludeInRelease{2020/10/01}%
                  {\shipout}{Hook management (shipout)}%
 \ExplSyntaxOn
@@ -13670,6 +14626,47 @@ of this package available from CTAN}
    \xe@alloc@intercharclass=\thr@@
  \fi
 \EndIncludeInRelease
+\ifx\directlua\@undefined
+\else
+  \directlua{%
+    if luatexbase.callbacktypes['input_level_string'] and %
+       luatexbase.in_callback('input_level_string','tracingstacklevels') then
+        luatexbase.remove_from_callback('input_level_string','tracingstacklevels')
+    end}%
+\fi
+\IncludeInRelease{2021/06/01}{trace_stack_levels}%
+                 {Lua trace_stack_levels function}%
+\ifx\directlua\@undefined
+\else
+    \directlua{%
+      local function trace_stack_levels (input_ptr)
+        local tracingstacklevels = tex.count.tracingstacklevels
+        if tex.tracingmacros > 0 or input_ptr < tracingstacklevels then
+          if tracingstacklevels > 0 then
+            if input_ptr < tracingstacklevels then
+              return "\string\n\string~" .. string.rep(".",input_ptr)
+            else
+              return "\string~\string~"
+            end
+          else
+            return "\string\n"
+          end
+        else
+          return ""
+        end
+      end
+    if luatexbase.callbacktypes['input_level_string'] then
+      luatexbase.add_to_callback('input_level_string',
+        trace_stack_levels,'tracingstacklevels')
+    end
+    }%
+\fi
+\EndIncludeInRelease
+
+\IncludeInRelease{0000/00/00}{trace_stack_levels}%
+                 {Lua trace_stack_levels function}%
+% Nothing here
+\EndIncludeInRelease
 \IncludeInRelease{2016/02/01}%
   {\XeTeXintercharclasses}{XeTeX character classes}%
   \ifx\XeTeXinterchartoks\undefined
@@ -13735,7 +14732,7 @@ of this package available from CTAN}
        {\document@default@language}{Save language for hyphenation}%
 \let\document@default@language\@undefined
 \EndIncludeInRelease
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\pdfgentounicode}{Preload glyphtounicode}%
 \ifx \pdfgentounicode \@undefined \else
     \input glyphtounicode
@@ -13875,6 +14872,21 @@ of this package available from CTAN}
   \let\DeclareFontEncoding@saved\@undefined
   \let\inputencodingname\@undefined
 \EndIncludeInRelease
+\@ifundefined{ExplSyntaxOn}%
+  {\let\ExplSyntaxOn\@undefined
+   \let\ExplSyntaxOff\@undefined
+   \@gobble}%
+  {\ExplSyntaxOn
+   \@firstofone}%
+  {%
+\tl_map_inline:Nn \l__latexrelease_restores_tl
+  {
+    \cs_set_eq:Nc #1 { __latexrelease_ \cs_to_str:N #1 }
+    \cs_undefine:c { __latexrelease_ \cs_to_str:N #1 }
+  }
+\tl_clear:N \l__latexrelease_restores_tl
+\msg_redirect_name:nnn { hooks } { exists } { }
+  \ExplSyntaxOff}%
 \endinput
 %%
 %% End of file `latexrelease.sty'.
diff --git a/Master/texmf-dist/tex/latex-dev/base/letter.cls b/Master/texmf-dist/tex/latex-dev/base/letter.cls
index 34a7ae4b023..587e999eebc 100644
--- a/Master/texmf-dist/tex/latex-dev/base/letter.cls
+++ b/Master/texmf-dist/tex/latex-dev/base/letter.cls
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 \NeedsTeXFormat{LaTeX2e}[1996/06/01]
 \ProvidesClass{letter}
-              [2021/01/07 v1.3c
+              [2021/03/05 v1.3c
                Standard LaTeX document class]
 \newcommand\@ptsize{}
 \DeclareOption{a4paper}
diff --git a/Master/texmf-dist/tex/latex-dev/base/ltluatex.lua b/Master/texmf-dist/tex/latex-dev/base/ltluatex.lua
index ee7fcd3df22..193514467b2 100644
--- a/Master/texmf-dist/tex/latex-dev/base/ltluatex.lua
+++ b/Master/texmf-dist/tex/latex-dev/base/ltluatex.lua
@@ -324,6 +324,7 @@ local callbacktypes = callbacktypes or {
   glyph_stream_provider           = exclusive,
   make_extensible                 = exclusive,
   font_descriptor_objnum_provider = exclusive,
+  input_level_string              = exclusive,
 }
 luatexbase.callbacktypes=callbacktypes
 local callback_register = callback_register or callback.register
diff --git a/Master/texmf-dist/tex/latex-dev/base/ltluatex.tex b/Master/texmf-dist/tex/latex-dev/base/ltluatex.tex
index 74e4779a415..90b6d2dfe7e 100644
--- a/Master/texmf-dist/tex/latex-dev/base/ltluatex.tex
+++ b/Master/texmf-dist/tex/latex-dev/base/ltluatex.tex
@@ -47,7 +47,7 @@
   #1#2[#3]{\endgroup\immediate\write-1{File: #1 #3}}
 \fi
 \ProvidesFile{ltluatex.tex}%
-[2021/01/15 v1.1s
+[2021/04/18 v1.1t
   LuaTeX support for plain TeX (core)
 ]
 \edef\etatcatcode{\the\catcode`\@}
diff --git a/Master/texmf-dist/tex/latex-dev/base/ltpara.ltx b/Master/texmf-dist/tex/latex-dev/base/ltpara.ltx
deleted file mode 100644
index b56859f471e..00000000000
--- a/Master/texmf-dist/tex/latex-dev/base/ltpara.ltx
+++ /dev/null
@@ -1,171 +0,0 @@
-%%
-%% This is file `ltpara.ltx',
-%% generated with the docstrip utility.
-%%
-%% The original source files were:
-%%
-%% ltpara.dtx  (with options: `2ekernel')
-%% 
-%% This is a generated file.
-%% 
-%% The source is maintained by the LaTeX Project team and bug
-%% reports for it can be opened at https://latex-project.org/bugs.html
-%% (but please observe conditions on bug reports sent to that address!)
-%% 
-%% 
-%% Copyright (C) 1993-2021
-%% The LaTeX Project and any individual authors listed elsewhere
-%% in this file.
-%% 
-%% This file was generated from file(s) of the LaTeX base system.
-%% --------------------------------------------------------------
-%% 
-%% It may be distributed and/or modified under the
-%% conditions of the LaTeX Project Public License, either version 1.3c
-%% of this license or (at your option) any later version.
-%% The latest version of this license is in
-%%    https://www.latex-project.org/lppl.txt
-%% and version 1.3c or later is part of all distributions of LaTeX
-%% version 2008 or later.
-%% 
-%% This file has the LPPL maintenance status "maintained".
-%% 
-%% This file may only be distributed together with a copy of the LaTeX
-%% base system. You may however distribute the LaTeX base system without
-%% such generated files.
-%% 
-%% The list of all files belonging to the LaTeX base distribution is
-%% given in the file `manifest.txt'. See also `legal.txt' for additional
-%% information.
-%% 
-%% The list of derived (unpacked) files belonging to the distribution
-%% and covered by LPPL is defined by the unpacking scripts (with
-%% extension .ins) which are part of the distribution.
-%% File: ltpara.dtx (C) Copyright 2020-2021
-%%% From File: lthooks.dtx
-\def\ltparaversion{v1.0d}
-\def\ltparadate{2021/02/18}
-
-
-\ExplSyntaxOn
-
-\hook_new_pair:nn{para/before}{para/after}
-\hook_new_pair:nn{para/begin}{para/end}
-\let \@kernel@before@para@before \@empty
-\let \@kernel@before@para@begin  \@empty
-\let \@kernel@after@para@end     \@empty
-\let \@kernel@after@para@after   \@empty
-\tl_new:N \g__para_standard_everypar_tl
-\tl_gset:Nn \g__para_standard_everypar_tl {
-  \box_gset_to_last:N \g_para_indentation_box
-  \group_begin:
-    \tex_par:D
-  \group_end:
-  \tex_everypar:D { \__kernel_msg_error:nnnn {para}{mode}{before}{vertical} }
-  \@kernel@before@para@before
-  \hook_use:n {para/before}
-  \group_begin:
-    \tex_everypar:D {}
-    \skip_zero:N \tex_parskip:D
-    \tex_noindent:D
-  \group_end:
-  \tex_everypar:D{\g__para_standard_everypar_tl}
-  \cs_set_eq:NN \__para_handle_indent: \__para_add_indentation_box:
-  \@kernel@before@para@begin
-  \hook_use:n {para/begin}
-  \if_mode_horizontal: \else:
-    \__kernel_msg_error:nnnn {para}{mode}{begin}{vertical} \fi:
-  \__para_handle_indent:
-}
-\tex_everypar:D{\g__para_standard_everypar_tl}
-\newtoks \everypar
-
-\tl_gput_right:Nx \g__para_standard_everypar_tl {
-    \exp_not:N \the
-    \exp_not:N \toks
-    \the \allocationnumber
-    \c_space_tl
-}
-\box_new:N \g_para_indentation_box
-
-\cs_new:Npn \__para_add_indentation_box: {
-  \box_use_drop:N \g_para_indentation_box
-}
-\cs_new_eq:NN \__para_handle_indent: \__para_add_indentation_box:
-\cs_new:Npn \para_suppress_indentation: {
-  \cs_set_eq:NN \__para_handle_indent: \prg_do_nothing:
-}
-\cs_set_eq:NN \IndentationBox \g_para_indentation_box
-\cs_set_eq:NN \SuppressIndentationBox \para_suppress_indentation:
-\cs_new_protected:Npn \para_end: {
-  \mode_if_horizontal:TF {
-    \mode_if_inner:F {
-         \tex_unskip:D
-         \hook_use:n{para/end}
-         \@kernel@after@para@end
-         \mode_if_horizontal:TF {
-           \if_int_compare:w 0 < \tex_lastnodetype:D
-             \tex_kern:D \c_zero_dim
-           \fi:
-           \tex_par:D
-           \hook_use:n{para/after}
-           \@kernel@after@para@after
-         }
-         { \__kernel_msg_error:nnnn {para}{mode}{end}{horizontal} }
-    }
-  }
-  \tex_par:D
-}
-\cs_set_eq:NN \par     \para_end:
-\cs_set_eq:NN \@@par   \para_end:
-\cs_set_eq:NN \endgraf \para_end:
-\everypar{\@nodocument} %% To get an error if text appears before the
-\__kernel_msg_new:nnnn {para} {mode}
-  {
-    Illegal~mode~ change~ in~ hook~ 'para/#1'.\\
-    Hook~ code~ did~ not~ remain~ in~ #2~ mode.
-  }
-  {
-    Paragraph~ hooks~ cannot~ change~ the~ TeX~ mode~ without~ causing~
-    endless~ recursion.~ The~ hook~ code~ in~ 'para/#1'~ needs~ to~ stay~
-    in~ #2~ mode,~ but~ it~ didn't.~ Examine~ the~ hook~
-    code~ with~ \ShowHook~ to~ find~ the~ issue.
-  }
-\ExplSyntaxOff
-\IfFormatAtLeastTF{2021/05/01}{}
-{
-\long\def \@savemarbox #1#2{%
-  \global\setbox #1%
-    \color@vbox
-      \vtop{%
-        \hsize\marginparwidth
-        \@parboxrestore
-        \@marginparreset
-        #2\par                    % <-- needed
-        \@minipagefalse
-        \outer@nobreak
-        }%
-    \color@endbox
-}
-\newcounter{paracnt}
-\def\@kernel@before@para@begin{%
-  \stepcounter{paracnt}%
-  \typeout{PARA: \arabic{paracnt} start
-    (\@currenvir\space level\on@line)}%
-}
-\def\@kernel@after@para@end  {%
-  \typeout{PARA: \arabic{paracnt} end \space\space
-    (\@currenvir\space level\on@line)}%
-  \addtocounter{paracnt}{-1}%
-}
-\let\color@begingroup\begingroup
-\def\color@endgroup{\endgraf\endgroup}
-\def\color@setgroup{\color@begingroup}  % \def\color@setgroup{\color@begingroup\set@color}
-\def\color@hbox{\hbox\bgroup\color@begingroup}
-\def\color@vbox{\vbox\bgroup\color@begingroup}
-\def\color@endbox{\color@endgroup\egroup}
-}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\endinput
-%%
-%% End of file `ltpara.ltx'.
diff --git a/Master/texmf-dist/tex/latex-dev/base/omlenc.def b/Master/texmf-dist/tex/latex-dev/base/omlenc.def
index 3b3ea0cbfc3..bf1bebaba3d 100644
--- a/Master/texmf-dist/tex/latex-dev/base/omlenc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/omlenc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{omlenc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \DeclareFontEncoding{OML}{}{}
 \DeclareTextSymbol{\textless}{OML}{`\<}
diff --git a/Master/texmf-dist/tex/latex-dev/base/omsenc.def b/Master/texmf-dist/tex/latex-dev/base/omsenc.def
index 10f60116098..c07656fd9d4 100644
--- a/Master/texmf-dist/tex/latex-dev/base/omsenc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/omsenc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{omsenc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \DeclareFontEncoding{OMS}{}{}
 \DeclareTextSymbol{\textasteriskcentered}{OMS}{3}   % "03
diff --git a/Master/texmf-dist/tex/latex-dev/base/ot1enc.def b/Master/texmf-dist/tex/latex-dev/base/ot1enc.def
index 00c70e7e971..7ee4e30b0a8 100644
--- a/Master/texmf-dist/tex/latex-dev/base/ot1enc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/ot1enc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{ot1enc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \DeclareFontEncoding{OT1}{}{}
 \DeclareTextAccent{\"}{OT1}{127}
diff --git a/Master/texmf-dist/tex/latex-dev/base/ot4enc.def b/Master/texmf-dist/tex/latex-dev/base/ot4enc.def
index bb1644e5b28..73b55c8f0a2 100644
--- a/Master/texmf-dist/tex/latex-dev/base/ot4enc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/ot4enc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{ot4enc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \DeclareFontEncoding{OT4}{}{}
 \DeclareFontSubstitution{OT4}{cmr}{m}{n}
diff --git a/Master/texmf-dist/tex/latex-dev/base/structuredlog.sty b/Master/texmf-dist/tex/latex-dev/base/structuredlog.sty
index e945e76549d..8257719886b 100644
--- a/Master/texmf-dist/tex/latex-dev/base/structuredlog.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/structuredlog.sty
@@ -42,8 +42,8 @@
 %% and covered by LPPL is defined by the unpacking scripts (with
 %% extension .ins) which are part of the distribution.
 %%% From File: ltfilehook.dtx
-\providecommand\ltfilehookversion{v1.0g}
-\providecommand\ltfilehookdate{2021/02/08}
+\providecommand\ltfilehookversion{v1.0j}
+\providecommand\ltfilehookdate{2021/04/29}
 \ProvidesExplPackage
     {structuredlog}{\ltfilehookdate}{\ltfilehookversion}
     {Structuring the TeX transcript file}
diff --git a/Master/texmf-dist/tex/latex-dev/base/t1enc.def b/Master/texmf-dist/tex/latex-dev/base/t1enc.def
index f59a16678ed..dad5bdd3733 100644
--- a/Master/texmf-dist/tex/latex-dev/base/t1enc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/t1enc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{t1enc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \DeclareFontEncoding{T1}{}{}
 \DeclareTextAccent{\`}{T1}{0}
diff --git a/Master/texmf-dist/tex/latex-dev/base/textcomp-2018-08-11.sty b/Master/texmf-dist/tex/latex-dev/base/textcomp-2018-08-11.sty
index 947c26fb0b3..57659edefc1 100644
--- a/Master/texmf-dist/tex/latex-dev/base/textcomp-2018-08-11.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/textcomp-2018-08-11.sty
@@ -42,7 +42,6 @@
 %% and covered by LPPL is defined by the unpacking scripts (with
 %% extension .ins) which are part of the distribution.
 %%% From File: lttextcomp.dtx
-
 \ProvidesPackage{textcomp}
    [2018/08/11 v2.0j Standard LaTeX package]
 
diff --git a/Master/texmf-dist/tex/latex-dev/base/textcomp.sty b/Master/texmf-dist/tex/latex-dev/base/textcomp.sty
index 8db7c8b1d86..dd443d4ccf4 100644
--- a/Master/texmf-dist/tex/latex-dev/base/textcomp.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/textcomp.sty
@@ -42,7 +42,6 @@
 %% and covered by LPPL is defined by the unpacking scripts (with
 %% extension .ins) which are part of the distribution.
 %%% From File: lttextcomp.dtx
-
 \providecommand\DeclareRelease[3]{}
 \providecommand\DeclareCurrentRelease[2]{}
 
diff --git a/Master/texmf-dist/tex/latex-dev/base/tracefnt.sty b/Master/texmf-dist/tex/latex-dev/base/tracefnt.sty
index cd7f60a26d5..09146d4c0f0 100644
--- a/Master/texmf-dist/tex/latex-dev/base/tracefnt.sty
+++ b/Master/texmf-dist/tex/latex-dev/base/tracefnt.sty
@@ -44,7 +44,7 @@
 %%% From File: ltfsstrc.dtx
 %% Copyright (C) 1989-97 by Frank Mittelbach and Rainer Sch\"opf.
 %% Copyright (C) 1994-97 by LaTeX Project. All rights reserved.
-\NeedsTeXFormat{LaTeX2e}[2021/05/01]
+\NeedsTeXFormat{LaTeX2e}[2021/06/01]
 \ProvidesPackage{tracefnt}
      [2020/12/22 v3.0n  Standard LaTeX package (font tracing)]
 \newcount\tracingfonts
@@ -126,6 +126,7 @@
       \fi
       \let\delayed@f@adjustment\@empty
     \fi
+    \@forced@seriesfalse
     \xdef\font@name{%
       \csname\curr@fontshape/\f@size\endcsname}%
     \pickup@font
@@ -137,7 +138,7 @@
 \AddToHook{selectfont}
    {\ifnum \tracingfonts>\tw@
        \@font@info{Switching to \font@name}\fi}
-\IncludeInRelease{2021/05/01}%
+\IncludeInRelease{2021/06/01}%
                  {\selectfont}{Add hook to \selectfont}%
 \EndIncludeInRelease
 \IncludeInRelease{0000/00/00}%
diff --git a/Master/texmf-dist/tex/latex-dev/base/tuenc.def b/Master/texmf-dist/tex/latex-dev/base/tuenc.def
index 90ebea4f728..3bddf30c999 100644
--- a/Master/texmf-dist/tex/latex-dev/base/tuenc.def
+++ b/Master/texmf-dist/tex/latex-dev/base/tuenc.def
@@ -43,7 +43,7 @@
 %% extension .ins) which are part of the distribution.
 %%% From File: ltoutenc.dtx
 \ProvidesFile{tuenc.def}
- [2021/02/19 v2.0u
+ [2021/04/29 v2.0v
       Standard LaTeX file]
 \providecommand\UnicodeEncodingName{TU}
 \begingroup\expandafter\expandafter\expandafter\endgroup
@@ -488,8 +488,14 @@
 \DeclareUnicodeComposite{\v}             {o}{"01D2}
 \DeclareUnicodeComposite{\v}             {U}{"01D3}
 \DeclareUnicodeComposite{\v}             {u}{"01D4}
+\DeclareUnicodeComposite{\'}             \AE{"01FC}
+\DeclareUnicodeComposite{\'}             {Æ}{"01FC}
+\DeclareUnicodeComposite{\'}             \ae{"01FD}
+\DeclareUnicodeComposite{\'}             {æ}{"01FD}
 \DeclareUnicodeComposite{\=}             \AE{"01E2}
+\DeclareUnicodeComposite{\=}             {Æ}{"01E2}
 \DeclareUnicodeComposite{\=}             \ae{"01E3}
+\DeclareUnicodeComposite{\=}             {æ}{"01E3}
 \DeclareUnicodeComposite{\v}             {G}{"01E6}
 \DeclareUnicodeComposite{\v}             {g}{"01E7}
 \DeclareUnicodeComposite{\v}             {K}{"01E8}
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/color.sty b/Master/texmf-dist/tex/latex-dev/graphics/color.sty
index 0f0b974689a..23c90207aa8 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/color.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/color.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% color.dtx Copyright (C) 1994--1999 David Carlisle
-%%           Copyright (C) 2005-2020 David Carlisle, LaTeX3 Project
+%%           Copyright (C) 2005-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/dvipdf.def b/Master/texmf-dist/tex/latex-dev/graphics/dvipdf.def
index 39d2d8f9835..04f533c35ae 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/dvipdf.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/dvipdf.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/dvipsnam.def b/Master/texmf-dist/tex/latex-dev/graphics/dvipsnam.def
index 06e7398272f..826161736cd 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/dvipsnam.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/dvipsnam.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/dvipsone.def b/Master/texmf-dist/tex/latex-dev/graphics/dvipsone.def
index b942a05ae3f..4918f74ba1f 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/dvipsone.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/dvipsone.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/dviwin.def b/Master/texmf-dist/tex/latex-dev/graphics/dviwin.def
index 07a34e4db2b..db6eac4074a 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/dviwin.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/dviwin.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/emtex.def b/Master/texmf-dist/tex/latex-dev/graphics/emtex.def
index c3d17aa20d0..d1d405dae14 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/emtex.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/emtex.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/epsfig.sty b/Master/texmf-dist/tex/latex-dev/graphics/epsfig.sty
index 114460d3493..bb0abac3949 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/epsfig.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/epsfig.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% epsfig.dtx Copyright (C) 1994-1996 1999 Sebastian Rahtz
-%%            Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%            Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/graphics-2017-06-25.sty b/Master/texmf-dist/tex/latex-dev/graphics/graphics-2017-06-25.sty
index 5cfa5df4500..154867d99a4 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/graphics-2017-06-25.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/graphics-2017-06-25.sty
@@ -12,7 +12,7 @@
 %%
 %%
 %% graphics.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
-%%              Copyright (C) 1995--2017 David Carlisle, LaTeX3 Project
+%%              Copyright (C) 1995--2017 David Carlisle, LaTeX Project
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/graphics.sty b/Master/texmf-dist/tex/latex-dev/graphics/graphics.sty
index 86e3314d9a5..5d0292c3d08 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/graphics.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/graphics.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% graphics.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
-%%              Copyright (C) 1995-2020 David Carlisle, LaTeX3 Project
+%%              Copyright (C) 1995-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
@@ -29,7 +31,7 @@
 \DeclareCurrentRelease{}{2019-10-01}
 
 \ProvidesPackage{graphics}
-          [2020/08/30 v1.4c  Standard LaTeX Graphics (DPC,SPQR)]
+          [2021/03/04 v1.4d  Standard LaTeX Graphics (DPC,SPQR)]
 \edef\Gin@codes{%
  \catcode`\noexpand\^^A\the\catcode`\^^A\relax
  \catcode`\noexpand\"\the\catcode`\"\relax
@@ -202,7 +204,7 @@
     \ifx\filename@ext\relax
       \let\filename@ext\Gin@gzext
     \else
-      \edef\Gin@ext{\Gin@ext\Gin@sepdefault\Gin@gzext}%
+      \edef\filename@ext{\filename@ext\Gin@sepdefault\Gin@gzext}%
     \fi
   \fi
   \ifx\filename@ext\relax
@@ -216,9 +218,10 @@
         \ifx\Gin@ext\relax 1%
         \else \@ifundefined{Gin@rule@\Gin@ext}{1}{0}%
         \fi >0
-      \let\Gin@ext\relax
+      \let\Gin@extsaved\Gin@ext
       \let\Gin@savedbase\filename@base
       \let\Gin@savedext\filename@ext
+      \let\Gin@ext\relax
       \edef\filename@base{\filename@base\Gin@sepdefault\filename@ext}%
       \let\filename@ext\relax
       \@for\Gin@temp:=\Gin@extensions\do{%
@@ -226,6 +229,7 @@
             \Gin@getbase\Gin@temp
           \fi}%
       \ifx\Gin@ext\relax
+        \let\Gin@ext\Gin@extsaved
         \let\filename@base\Gin@savedbase
         \let\filename@ext\Gin@savedext
       \fi
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/graphicx.sty b/Master/texmf-dist/tex/latex-dev/graphics/graphicx.sty
index 9446a0a5c2f..0a259c8836f 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/graphicx.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/graphicx.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% graphicx.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
-%%              Copyright (C) 1995-2020 David Carlisle, LaTeX3 Project
+%%              Copyright (C) 1995-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
@@ -21,7 +23,7 @@
 %%
 \NeedsTeXFormat{LaTeX2e}[1995/12/01]
 \ProvidesPackage{graphicx}
-          [2020/09/09 v1.2b  Enhanced LaTeX Graphics (DPC,SPQR)]
+          [2020/12/05 v1.2c  Enhanced LaTeX Graphics (DPC,SPQR)]
 \DeclareOption{unknownkeysallowed}
   {\PassOptionsToPackage\CurrentOption{keyval}}
 \DeclareOption*{\PassOptionsToPackage\CurrentOption{graphics}}
@@ -99,7 +101,7 @@
 \define@key{Gin}{decodearray}{%
   \def\Gin@decode{#1}%
 }
-\define@key{Gin}{quiet}{%
+\define@key{Gin}{quiet}[]{%
   \let\Gin@log\@gobble
 }
 \define@key{Gin}{page}{%
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/keyval.sty b/Master/texmf-dist/tex/latex-dev/graphics/keyval.sty
index ddb6c0a183e..97bbda4f480 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/keyval.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/keyval.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% keyval.dtx Copyright (C) 1993 1994 1995 1997 1998 1999 David Carlisle
-%%            Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%            Copyright (C) 2000-2021 David Carlisle, LaTeX Project
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/lscape.sty b/Master/texmf-dist/tex/latex-dev/graphics/lscape.sty
index d9f2daee5a8..25342e422fc 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/lscape.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/lscape.sty
@@ -12,7 +12,9 @@
 %% 
 %% 
 %% lscape.dtx Copyright (C) 1994 1999-2000 David Carlisle
-%%            Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%            Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/pctex32.def b/Master/texmf-dist/tex/latex-dev/graphics/pctex32.def
index 58c913cd023..5934c4c0a94 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/pctex32.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/pctex32.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/pctexhp.def b/Master/texmf-dist/tex/latex-dev/graphics/pctexhp.def
index 341204427d1..76e83d251c4 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/pctexhp.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/pctexhp.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/pctexps.def b/Master/texmf-dist/tex/latex-dev/graphics/pctexps.def
index 6920dcd739e..85f6f3a13de 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/pctexps.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/pctexps.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/pctexwin.def b/Master/texmf-dist/tex/latex-dev/graphics/pctexwin.def
index 198644d3b3b..cf44d184547 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/pctexwin.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/pctexwin.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/rotating.sty b/Master/texmf-dist/tex/latex-dev/graphics/rotating.sty
index 14ba6fb1427..7f3a2df8f47 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/rotating.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/rotating.sty
@@ -11,9 +11,11 @@
 %% (but please observe conditions on bug reports sent to that address!)
 %% 
 %% 
-%% Copyright (C) 1995--1999 Sebastian Rahtz and Leonor Barroca
-%% Copyright (C) 2001--2003,2007--2009 Robin Fairbairns
-%% Copyright (C) 2016-2020 LaTeX3 Project
+%% Copyright (C) 1995-1999 Sebastian Rahtz and Leonor Barroca
+%% Copyright (C) 2001-2003,2007-2009 Robin Fairbairns
+%% Copyright (C) 2016-2021 LaTeX Project
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{rotating}%
     [2016/08/11 v2.16d
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/tcidvi.def b/Master/texmf-dist/tex/latex-dev/graphics/tcidvi.def
index d4a93d43c38..805384f66e7 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/tcidvi.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/tcidvi.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/trig.sty b/Master/texmf-dist/tex/latex-dev/graphics/trig.sty
index 1cdc14cb7e3..1147ab46c79 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/trig.sty
+++ b/Master/texmf-dist/tex/latex-dev/graphics/trig.sty
@@ -11,8 +11,10 @@
 %% (but please observe conditions on bug reports sent to that address!)
 %% 
 %% 
-%% File: trig.dtx Copyright (C) 1993 1994 1995 1996 1997 1999 David Carlisle
-%%                Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%% File: trig.dtx Copyright (C) 1993-1999 David Carlisle
+%%                Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/graphics/truetex.def b/Master/texmf-dist/tex/latex-dev/graphics/truetex.def
index 62a4742b863..a2d0fc970ea 100644
--- a/Master/texmf-dist/tex/latex-dev/graphics/truetex.def
+++ b/Master/texmf-dist/tex/latex-dev/graphics/truetex.def
@@ -8,7 +8,9 @@
 %% 
 %% drivers.dtx Copyright (C) 1994      David Carlisle Sebastian Rahtz
 %%             Copyright (C) 1995 1996 1997 1998 1999 David Carlisle
-%%             Copyright (C) 2000-2020 David Carlisle, LaTeX3 Project
+%%             Copyright (C) 2000-2021
+%% The LaTeX Project and any individual authors listed elsewhere
+%% in this file.
 %%
 %% This file is part of the Standard LaTeX `Graphics Bundle'.
 %% It may be distributed under the terms of the LaTeX Project Public
diff --git a/Master/texmf-dist/tex/latex-dev/tools/array.sty b/Master/texmf-dist/tex/latex-dev/tools/array.sty
index 8fae23a89e9..80b0241e965 100644
--- a/Master/texmf-dist/tex/latex-dev/tools/array.sty
+++ b/Master/texmf-dist/tex/latex-dev/tools/array.sty
@@ -46,7 +46,7 @@
 \DeclareCurrentRelease{}{2020-10-01}
 
 \ProvidesPackage{array}
-         [2021/02/10 v2.5d Tabular extension package (FMi)]
+         [2021/04/20 v2.5e Tabular extension package (FMi)]
 %%
 
 \def\@addtopreamble#1{\xdef\@preamble{\@preamble #1}}
@@ -184,7 +184,7 @@
 \newdimen \extrarowheight
 \extrarowheight=0pt
 \def\@arstrut{\unhcopy\@arstrutbox}
-\def\@arraycr{\relax\iffalse{\fi\ifnum 0=`}\fi
+\protected\def\@arraycr{\relax\iffalse{\fi\ifnum 0=`}\fi
   \@ifstar \@xarraycr \@xarraycr}
 \def\@xarraycr{\@ifnextchar [%
   \@argarraycr {\ifnum 0=`{}\fi\cr}}
diff --git a/Master/texmf-dist/tex/latex-dev/tools/bm.sty b/Master/texmf-dist/tex/latex-dev/tools/bm.sty
index b98b7ed2049..18b4c0c9661 100644
--- a/Master/texmf-dist/tex/latex-dev/tools/bm.sty
+++ b/Master/texmf-dist/tex/latex-dev/tools/bm.sty
@@ -40,11 +40,17 @@
 %% Development of this package was commissioned by Y&Y Inc.
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{bm}
-          [2019/07/24 v1.2d Bold Symbol Support (DPC/FMi)]
-\def\bm#1#2{%
-  \let\bm@pmb\install@mathalphabet
-  \let\bm@pmb@\getanddefine@fonts
-  \let\bm@pmb@@\or
+          [2021/04/25 v1.2e Bold Symbol Support (DPC/FMi)]
+\DeclareOption{nopmb}{\let\bm@pmb@\@firstofone}
+\DeclareOption{warn}{\def\bm@info{\PackageWarningNoLine{bm}}}
+\DeclareOption{info}{\def\bm@info#1{\PackageInfo{bm}{#1\@gobble}}}
+\DeclareOption{silent}{\let\bm@info\@gobble}
+\ExecuteOptions{info}
+\ProcessOptions\relax
+\def\bm@setup#1#2{%
+  \let\bm@install@mathalphabet\install@mathalphabet
+  \let\bm@getanddefine@fonts\getanddefine@fonts
+  \let\bm@or\or
   \edef\bm@general{\f@encoding/\f@family/\f@series/\f@shape/\f@size}%
   \@tempcnta#2%
   \count@-\count18%
@@ -65,6 +71,8 @@
       \@tempb\csname mv@#1\endcsname\@nil
     \ifx\@tempa\@tempb
       \bm@define\m@ne
+      \bm@info{No #1 for \string##2%
+               \ifx\bm@pmb@\@firstofone\else, using \string\pmb\fi}%
     \else
       \edef\@tempa{sym#1\expandafter\@gobblefour\string##1}%
       \ifnum\@tempcnta<%
@@ -105,7 +113,7 @@
            \fi
          \fi
         \else
-          \PackageInfo{bm}%
+          \bm@info
             {Symbol font \@tempa\space already defined.\MessageBreak
              Not overwriting it}%
         \fi
@@ -123,9 +131,9 @@
       \z@
     \noexpand\fi}%
   \expandafter\split@name\bm@general\@nil
-  \let\install@mathalphabet\bm@pmb
-  \let\getanddefine@fonts\bm@pmb@
-  \let\or\bm@pmb@@}
+  \let\install@mathalphabet\bm@install@mathalphabet
+  \let\getanddefine@fonts\bm@getanddefine@fonts
+  \let\or\bm@or}
 \ifx\bmmax\@undefined
   \chardef\bmmax=4
 \fi
@@ -133,9 +141,9 @@
   \def\bm@boldtable{\m@ne}
   \AtEndOfPackage{%
     \def\bm@gr@up#1#2{%
-      \bm@pmb{#2}}}
+      \bm@install@mathalphabet{#2}}}
 \else
-  \bm{bold}\bmmax
+  \bm@setup{bold}\bmmax
   \@ifundefined{symboldoperators}
     {}
     {\DeclareSymbolFontAlphabet\mathbf{boldoperators}}
@@ -145,7 +153,7 @@
 \fi
 \ifx\mv@heavy\@undefined
 \else
-  \bm{heavy}\hmmax
+  \bm@setup{heavy}\hmmax
 \fi
 \begingroup
 \catcode`\'=\active
@@ -176,6 +184,7 @@
         \expandafter\@secondoftwo
       \fi
       {##2##4}{##3{##4}}}%
+    \let\kernel@ifnextchar\@ifnextchar
     \def\GenericWarning##1##2{%
       \unvcopy{\GenericWarning{##1}{##2}}}%
     \def\GenericError##1##2##3##4{%
@@ -357,6 +366,7 @@
 \fi}
 \def\bm@pmb#1{%
   \bm@add{\bm@pmb@{#1}}}
+\ifx\bm@pmb@\@firstofone\else
 \def\bm@pmb@#1{{%
   \setbox\tw@\hbox{$\m@th\mkern.4mu$}%
   \mathchoice
@@ -372,6 +382,7 @@
   \raise1.5\dimen@\rlap{\copy\z@}%
   \kern\dimen@
   \box\z@}}%
+\fi
 \def\bm@class{%
   \ifcase\count@
     \or
diff --git a/Master/texmf-dist/tex/latex-dev/tools/layout.sty b/Master/texmf-dist/tex/latex-dev/tools/layout.sty
index 354a79b9451..bf2d8584829 100644
--- a/Master/texmf-dist/tex/latex-dev/tools/layout.sty
+++ b/Master/texmf-dist/tex/latex-dev/tools/layout.sty
@@ -37,7 +37,7 @@
 %% 
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{layout}
-                [2020-07-25 v1.2d Show layout parameters]
+                [2021-03-10 v1.2e Show layout parameters]
 \DeclareOption{dutch}{%
   \def\Headertext{Kopregel}
   \def\Bodytext{Broodtekst}
@@ -104,6 +104,14 @@
   \def\oneinchtext{un pollice}
   \def\notshown{non mostrato}
   }
+\DeclareOption{romanian}{%
+  \def\Headertext{Antet}
+  \def\Bodytext{Corp}
+  \def\Footertext{Subsol}
+  \def\MarginNotestext{Note\\ Marginale}
+  \def\oneinchtext{un inch}
+  \def\notshown{neafi\textcommabelow sat}
+  }
 \DeclareOption{japanese}{%
   \def\Headertext{天}
   \def\Bodytext{基本版面}
diff --git a/Master/texmf-dist/tex/latex-dev/tools/longtable.sty b/Master/texmf-dist/tex/latex-dev/tools/longtable.sty
index 16eb6a57915..6c3dcc62fb9 100644
--- a/Master/texmf-dist/tex/latex-dev/tools/longtable.sty
+++ b/Master/texmf-dist/tex/latex-dev/tools/longtable.sty
@@ -39,11 +39,11 @@
 \providecommand\DeclareRelease[3]{}
 \providecommand\DeclareCurrentRelease[2]{}
 
-\DeclareRelease{}{2020-01-02}{longtable-2020-01-07.sty}
+\DeclareRelease{v4.13}{2020-01-02}{longtable-2020-01-07.sty}
 \DeclareCurrentRelease{}{2020-02-07}
 
 \ProvidesPackage{longtable}
-          [2020-02-07 v4.14 Multi-page Table package (DPC)]
+          [2021-04-21 v4.15 Multi-page Table package (DPC)]
 \def\LT@err{\PackageError{longtable}}
 \def\LT@warn{\PackageWarning{longtable}}
 \def\LT@final@warn{%
@@ -162,12 +162,13 @@
   \advance\dimen@ \ht\ifvoid\LT@firsthead\LT@head\else\LT@firsthead\fi
   \advance\dimen@ \dp\ifvoid\LT@firsthead\LT@head\else\LT@firsthead\fi
   \advance\dimen@ \ht\LT@foot
-  \dimen@ii\vfuzz
+  \edef\LT@reset@vfuzz{\vfuzz\the\vfuzz\vbadness\the\vbadness\relax}%
   \vfuzz\maxdimen
-    \setbox\tw@\copy\z@
-    \setbox\tw@\vsplit\tw@ to \ht\@arstrutbox
-    \setbox\tw@\vbox{\unvbox\tw@}%
-  \vfuzz\dimen@ii
+  \vbadness\@M
+  \setbox\tw@\copy\z@
+  \setbox\tw@\vsplit\tw@ to \ht\@arstrutbox
+  \setbox\tw@\vbox{\unvbox\tw@}%
+  \LT@reset@vfuzz
   \advance\dimen@ \ht
         \ifdim\ht\@arstrutbox>\ht\tw@\@arstrutbox\else\tw@\fi
   \advance\dimen@\dp
@@ -227,7 +228,7 @@
   \else
     \expandafter\LT@nofcols
   \fi}
-\def\LT@tabularcr{%
+\protected\def\LT@tabularcr{%
   \relax\iffalse{\fi\ifnum0=`}\fi
   \@ifstar
     {\def\crcr{\LT@crcr\noalign{\nobreak}}\let\cr\crcr
@@ -396,6 +397,7 @@
     {\egroup\@xdblarg{\LT@c@ption\@firstofone}}}
 \def\LT@makecaption#1#2#3{%
   \LT@mcol\LT@cols c{\hbox to\z@{\hss\parbox[t]\LTcapwidth{%
+    \reset@font
     \sbox\@tempboxa{#1{#2: }#3}%
     \ifdim\wd\@tempboxa>\hsize
       #1{#2: }#3%
@@ -459,7 +461,7 @@
   \the\LT@p@ftn
   \global\LT@p@ftn{}%
   \hfil}
-\def\LT@p@ftntext#1{%
+\long\def\LT@p@ftntext#1{%
   \edef\@tempa{\the\LT@p@ftn\noexpand\footnotetext[\the\c@footnote]}%
   \global\LT@p@ftn\expandafter{\@tempa{#1}}}%
 \endinput
diff --git a/Master/texmf-dist/tex/latex-dev/tools/trace.sty b/Master/texmf-dist/tex/latex-dev/tools/trace.sty
index 8306cf8465f..e43c50706bb 100644
--- a/Master/texmf-dist/tex/latex-dev/tools/trace.sty
+++ b/Master/texmf-dist/tex/latex-dev/tools/trace.sty
@@ -41,7 +41,7 @@
 %%
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{trace}
-          [2018/10/13 v1.1e trace LaTeX code]
+          [2021/04/18 v1.1f trace LaTeX code]
 \NeedsTeXFormat{LaTeX2e}[1998/12/01]
 \DeclareOption{logonly}
    {\let\tracingonline@p\z@}
@@ -57,19 +57,20 @@
              \tr@ce@n}
 
 %% \tracinglostchars\z@
-  \def\tr@ce@n{%
-    \@tracingtrue
+  \edef\tr@ce@n{%
+    \noexpand\@tracingtrue
     \tracingstats\tw@
     \tracingpages\@ne
-    \tracinglostchars\@ne
+    \tracinglostchars\thr@@
     \tracingparagraphs\@ne
     \errorcontextlines\maxdimen
-    \ifnum\tracingoutput=\@ne
-    \else
+    \ifdefined\tracingstacklevels \tracingstacklevels\maxdimen \fi
+    \noexpand\ifnum\tracingoutput=\@ne
+    \noexpand\else
       \tracingoutput\tw@
       \showboxbreadth\maxdimen
       \showboxdepth\maxdimen
-    \fi
+    \noexpand\fi
     \errorstopmode
     \tracingmacros\tw@
     \tracinggroups\@ne
@@ -78,18 +79,20 @@
     \tracingassigns\@ne
     \tracingonline\tracingonline@p
   }
-  \def\conditionally@traceoff{%
+  \edef\conditionally@traceoff{%
     \tracingassigns\z@
     \tracingrestores\z@
     \tracingcommands\z@
     \tracingpages\z@
     \tracingmacros\z@
-    \ifnum\tracingoutput=\tw@
+    \noexpand\ifnum\tracingoutput=\tw@
       \tracingoutput\z@
       \showboxbreadth\m@ne
       \showboxdepth\m@ne
-    \fi
+    \noexpand\fi
     \tracingstats\@ne
+    \ifdefined\tracingstacklevels \tracingstacklevels\z@ \fi
+    \errorcontextlines\m@ne
     \tracingparagraphs\z@
     \tracinggroups\z@
   }